Colleoe  Entrance  Examination  Boarb 


EXAMINATION  QUESTIONS 


OLOGY 
_  RAWING 


IN 

BOTANY 

GEOGRAPHY 

ZOOLOGY 


CHEMISTRY 
PHYSICS 


FOURTH  SERIES 


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College  Entranee  Eiamination  Boatb 


EXAMINATION  QUESTIONS 


BIOLOGY 
DRAWING 


IN 

BOTANY 

GEOGRAPHY 

ZOOLOGY 


CHEMISTRY 
PHYSICS 


FGURTH  SERIES 


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UMl'vnSRSIT 


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yELES 
UBKARY 

GINN  AND  COMPANY 

BOSTON    •     NEW  YORK    •    CHICAGO    •    LONDON' 
ATLANTA    •    DALLAS    •    COLUMBUS    •    SAN   FRANCLSCO 


105350 


Copyright,  1916, 1917, 1918, 1919,  1920 

BY  THE 

College  Entrance  Examination  Board 


ALL    RIGHTS   RESERVED 


Clie   fltl)tn»um   gre«< 

CINN   AND   COMPANY  •  PRO- 
PRIUTOKS  •  HOSroN  •  U.S.A. 


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PREFACE 

While  the  annual  volume  of  examination  questions  published  by  the 
College  Entrance  Examination  Board  has  met  the  needs  of  many  candi- 
dates for  examination  and  their  teachers,  the  Board  is  constantly  in  receipt 
of  communications  asking  for  the  questions  set  in  certain  subjects  in  suc- 
cessive years.  In  order  to  meet  this  demand  the  Board  has  prepared  pam- 
phlets containing  the  questions  in  certain  subjects  from  191 6  to  1920 
inclusive.    These  pamphlets  are  as  follows  : 

1.  Examination  questions  in  Latin  and  Greek,  19 16-1920. 

2.  Examination    questions    in    English    and    other   modern    languages, 

1916-1920. 

3.  Examination  questions  in  mathematics,  191 6-1920. 

4.  Examination  questions  in  history,   1916-1920. 

5.  Examination    questions    in    the    natural    sciences    and    in   drawing, 

1916-1920. 

Quite  apart  from  meeting  the  needs  of  candidates  for  examination 
and  their  teachers,  these  publications  ought  to  have  a  beneficial  influence 
upon  teaching  for  the  reason  that  they  illustrate  in  concrete  form  principles 
agreed  upon  by  many  leading  teachers  of  the  subjects  represented. 


CONTENTS 


PAGE 


Biology 7 

Botany .     .  15 

Chemistry 25 

Comprehensive 37 

Drawing  —  Freehand 63 

Drawing  —  Mechanical 79 

Geography 95 

Physics 105 

Comprehensive 117 

Zoology 1 45 


BIOLOGY 


1916 
BIOLOGY 

Friday  9:00  a.m.    Two  hours 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  part 
of  the  examination. 

Answer  two  questions  from  each  group  and  four  additional  questions  which  may  be 
selected  from  any  group.  Up 

Group  I 

1.  Describe  a  cell  indicating — 

(a)  the  parts  which  are  common  to  both  plant  and  animal  cells; 

(b)  the  parts  peculiar  to  certain  animal  cells; 

(c)  the  parts  pecuhar  to  certain  plant  cells. 

2.  Explain  in  detail  the  structure  of  some  seed. 

3.  Select  a  protozoan,  a  clam,  a  grasshopper,  a  frog,  or  a  cat,  and  describe  the 

organs  by  which  it  performs  the  following  functions: 

(a)  ingestion; 

(b)  locomotion; 

(c)  respiration; 

(d)  sensation. 

4.  Describe  the  structure  of  the  root  of  a  plant  and  explain  the  various  functions 

which  it  may  perform. 

5.  Compare  the  organs  of  locomotion  in — 

(a)  ameba; 

(b)  fish; 

(c)  frog; 

(d)  cat; 

(e)  bird.  <^ 

Group  II 

6.  What  similar  functions  does  water  perform  in  animals  and  plants  ? 

7.  Compare  the  metamorphosis  of  a  grasshopper  and  of  a  butterfly. 

8.  Explain  some  of  the  adaptations  of  flowers  to  cross-pollination. 

9.  Why  must  plants  and  animals  breathe  in  order  to  live  ? 

10.  Name  the  principal  phyla,  or  large  representative  groups,  of  plants  and  ani- 

mals, with  an  example  from  each  group. 

Group  III 

11.  Explain  what  is  meant  by — 

(a)  infection; 

(b)  quarantine; 

(c)  inoculation; 
id)  bacteria; 
(e)   antitoxin. 

12.  Xame  5  plants  and  5  animals  of  considerable  economic  importance,  each 

representing  a  different  class.     Show  how  each  is  useful  or  harmful. 

13.  Indicate  four  different  ways  in  which  food  may  be  kept  from  spoiUng,  stating 

the  biological  principle  involved  in  each  case. 

14.  What  part  do  soil  bacteria  play  in  agriculture? 

15.  For  what  are  three  of  the  following  men  famous:  Linnaeus,  Cuvier,  Harvey, 

Pasteur,  Darwin  ? 
8 


1917 
BIOLOGY 

Friday  2  p.m.     Two  hours 

Answer  two  questions  from  each  group,  and  four  additional  questions  which  may  be 
selected  from  any  of  the  groups. 

Group  I 

1.  Describe  the  microscopic  structure  of  the  leaf  of  a  flowering  plant,  indicating 

the  function  of  each  part. 

2.  Name  and  describe  the  reproductive  organs  in  a  flower  and  in  a  fish  (or  frog). 

3.  Describe  fully  three  adaptations  of  plants  for  seed  dispersal.     Give  illus- 

trative examples. 

4.  Compare  the  circulatory  system  of  man  and  some  animal  you  have  studied, 

pointing  out  the  resemblances  and  differences. 

5.  Compare  the  sense  organs  of  an  insect  and  of  a  vertebrate. 

Group  II 

6.  Explain  how  the  inorganic  substances  in  the  soil  are  absorbed  and  transported 

to  the  leaf. 

7.  What  are  the  differences  in  the  method  of  nutrition  in  a  green  plant  and  in 

man? 

8.  Show  how  each  of  the  following  organs  contributes  to  the  maintenance  of 

life  and  health:  salivary  glands,  pancreas,  liver,  kidneys,  small  intestine? 

9.  (a)  Give  the  distinguishing  characteristics  of  five  general  groups  of  animals. 
(b)  Give  the  distinguishing  characteristics  of  five  general  groups  of  plants. 

JO.  Describe  the  life  history  of  either  a  flowering  plant  or  a  frog. 

Group  III 

11.  Show  how  bacteria  are  essential  to  the  life  of  man. 

12.  Explain  fully  the  ways  in  which  a  knowledge  of  biology  might  be  of  impor- 

tance to  (a)  the  farmer,  (b)  the  baker,  (c)  the  butcher,  (d)  the  doctor. 

13.  What  is  the  economic  importance  of  five  of  the  following  organisms:   owl, 

flax,  skunk,  toad,  yeast,  white  daisy,  starfish  ? 

14.  (a)  In  what  ways  may  the  growth  of  bacteria  be  checked  without  killing 

them? 
{b)  In  what  ways  may  bacteria  be  killed  ? 

15.  In  what  ways  may  plant  or  animal  breeders  improve  their  stock  ? 


1918 

BIOLOGY 

Friday,  June  21  2  p.m.    Two  hours 

Answer  two  questions  from  each  group  and  four  additional  questions  which  may  be 
selected  from  any  of  the  groups. 

Group  I 

1.  Compare  bacteria,  yeasts,  and  molds. 

2.  (a)  Name  three  tissues  in  the  himian  body  that  have  to  do  with  the  function 

of  movement. 
(b)  How  is  each  tissue  specially  adapted  for  its  work  ? 

3.  Describe  the  structure  of  some  seed  and  explain  the  use  of  each  part. 

4.  Compare  the  respiratory  organs  of  a  tadpole,  a  frog,  and  a  man,  stating 

precisely  what  occurs  in  the  process  of  respiration. 

5.  Describe  the  principal  appendages  of  an  insect,  stating  the  function  of  each, 

and  naming  the  segment  of  the  body  to  which  each  is  attached. 

Group  II 

6.  Describe  the  process  of  reproduction  of  some  alga  which  you  have  studied. 

7.  Distinguish  between  the  terms  phylum  (or  branch),  class,  genus,  and  species. 

Illustrate  these  terms  by  giving  the  classification  of  some  animal  or  plant 
which  you  have  studied. 

8.  Trace  the  modifications  which  a  piece  of  meat  undergoes  in  being  incorporated 

into  the  tissues  of  the  human  body. 

9.  A  bean  seed  was  planted  in  May;  from  this  seed  a  vigorous  plant  developed 

and  reached  full  maturity  before  it  was  killed  by  frost  in  October.  State 
the  most  important  periods  of  development  and  the  chief  events  in  the 
life  of  this  plant,  noting  what  organs  were  most  conspicuous  at  each 
period. 

10.  Describe  the  biological  processes  involved  when  an  athlete  starts  to  run  at 

the  sound  of  a  pistol. 

Group  III 

11.  Show  how  molds  affect  human  welfare. 

12.  (a)  Distinguish  between  the  processes  of  fermentation  and  decomposition. 

(b)  Name  the  kind  of  organism  that  causes  each. 

(c)  State  how  each  process  is  of  use  to  man. 

13.  What  is  meant  by  Mendel's  Law  of  Heredity  ? 

14.  Outline  a  dinner  menu  which  is  in  accordance  with  war  conditions  and 

would  at  the  same  time  supply  adequate  nutrition  for  a  high-school  student. 
(Give  reasons  for  your  choice.) 

15.  (a)  Name  the  principal  infectious  diseases  which  may  be  obtained  from 

(1)  milk,  (2)  water,  (3)  dust  of  streets  and  pubhc  places. 
(6)  Show  how  infection  from  these  sources  may  be  prevented  by  the  individual 
and  by  the  civic  authorities. 


Page  1 

1919 
BIOLOGY 

Friday,  June  20  2  p.m.     Two  hours 

Answer  two  questions  from  each  group  and  four  additional  questions  which  may  be 
selected  from  any  of  the  groups.  Number  each  answer  to  correspond  with  the  question 
selected. 

Group  I 

1.  Make  a  labeled  drawing  of  a  typical  plant  cell. 

2.  Name  a  flower  and  an   insect  mutually  adapted  for  insect  pollination. 

Describe  the  structural  adaptations  in  both  flower  and  insect. 

3.  Name  and  locate  the  parts  of  a  tooth  shown  in  a  drawing  of  a  vertical 

section. 

4.  Describe  the  structure  of  some  protozoan  that  you  have  studied.     Explain 

how  this  organism  moves,  how  it  secures  its  food,  and  how  it  withstands 
adverse  conditions. 

5.  (a)  Describe  the  structure  of  your  hand. 

(b)  Name  all  the  tissues  of  which  it  is  composed. 

(c)  What  function  does  each  tissue  perform  ? 

(d)  In  what  ways  is  the  hand  adapted  for  its  work  ? 

Group  II 

6.  Explain  the  complete  path,  or  cycle,  by  which  a  molecule  of  free  nitrogen 

from  the  air  may  be  incorporated  into  the  living  tissue  of  a  man  and  may 
again  reach  the  atmosphere. 

7.  Name  five  vital  functions  of  a  fish  and  briefly  describe  the  mechanism  by 

means  of  which  each  of  these  functions  is  accomplished. 

8.  Describe  the  development  of  the  frog  or  toad  from  the  time  of  egg-laying  to 

the  adult  stage. 

9.  (a)  Trace  the  course  of  soil  water  from  its  entrance  into  a  living  plant  to  its 

exit  from  the  plant. 
(b)  Name  at  least  two  ways  in  which  the  plant  uses  soil  water. 

10.  Name  tlie  phylum  (branch)  and  class  of  each  of  the  following:   fern,  sun- 
flower, shark,  whale,  bacteria,  seal,  frog,  oak,  turtle,  grasshopper. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

Group  III 

11.  (a)  Name  two  diseases  the  germs  of  which  may  be  transmitted  through 

infected  milk  or  water. 
(b)  Explain  fully  the  method  of  prevention  for  one  of  these  diseases.  w^ 

12.  (a)  Mention  the  principal  organisms  which  may  render  each  of  the  following 

foods  unfit  for  human  use:  grain,  milk,  fruit,  meat. 
(b)  Explain  the  principles  involved  in  the  preservation  of  food  by  drying,  by 
canning,  by  refrigerating,  and  by  salting. 

13.  Describe  the  structure,  growth,  and  reproduction,  and  the  means  of  distribu- 

tion of  the  bread  mold. 

14.  (a)  What  is  the  probable  cause  of  influenza  ? 

(b)  How  is  the  infection  transmitted  ? 

(c)  What  precautions  have  scientific  value  ? 

(d)  WTiat  popular  precautions  are  useless  ? 

(e)  What  should  a  person  with  the  influenza  do  (1)  for  himself  ?   (2)  for  the 

community  ? 

15.  Mention  the  principal  organisms,  living  in  a  field,  which  are  of  service  to 

the  growing  crops  and  explain  why  each  is  beneficial.  ,^ 


«P 


Page  1 

1920 

BIOLOGY 

Friday,  June  25  2  p.m.    Two  hours 

Answer  two  questions  from  each  group  and  four  additional  questions  which  may  be 
selected  from  any  of  the  groups.  Number  each  answer  to  correspond  with  the  question 
selected. 


Group  I 

1.  Describe  fundamental  structural  differences  between  a  mold  and  a  fern. 

2.  Make  a  labeled  diagram  of  the  digestive  system  of  some  animal. 

3.  Define  the  following  terms  and  explain  where  each  structure  is  to  be  found: 

stoma,  nictitating  membrane,  cilium,  stamen,  chromosome,  protoplasm, 
petiole,  pulsating  vacuole,  tentacle,  endosperm. 

4.  Describe  the  composition  of  the  blood  and  explain  what  changes  it  undergoes 

in  the  lungs. 

5.  Make  a  diagram  showing  the  structure  of  a  root  and  explain  the  function  of 

each  part. 


Group  II 

6.  Explain  how  a  frog  or  toad  is  adapted  for  living  in  its  environment  during 

each  stage  of  its  life-history. 

7.  Describe  the  process  by  means  of  which  energy  is  stored  up  by  a  green  plant. 

8.  Name  three  animals  which  reproduce  in  a  strikingly  different  way  and 

explain  each  method. 

9.  Distinguish   between:     (a)   secretion  and   excretion;     (b)   absorption   and 

digestion;    (c)  respiration   and   inhalation;    (d)  motion  and  locomotion; 
(e)  saprophyte  and  parasite. 

10.  State  the  environmental  conditions  necessary  for  active  life. 
(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 
Group  III 

11.  (a)  In  what  different  ways  are  forests  of  importance  to  human  welfare  ? 

(b)  Name  the  most  important  enemies  of  forests. 

(c)  Outline  a  plan  by  which  forests  may  be  conserved. 

12.  Explain  the  method  by  which  an  improved  variety  of  plant  or  animal  could 

be  originated. 

13.  State  different  ways  in  which  insects  are  beneficial  to  man. 

14.  (a)  Criticize  the  following  luncheon  for  a  high-school  pupil,  giving  scientific 

reasons  for  your  answer:  bread  and  butter;  mashed  potatoes;  tapioca 
pudding;  candy. 

(b)  What  changes,  if  any,  would  you  make  in  the  above  ? 

(c)  Give  the  particular  use  to  the  body  of  each  nutrient  found  in  the  revised 

menu. 

15.  Discuss  the  relations  of  the  following  birds  to  man:  bobwhite,  crow,  robin, 

Enghsh  sparrow,  owl. 


u 


BOTANY 


»5 


1916 
BOTANY 

Friday  9:00  a.m.    Two  hours 

A  teacher's  certificate  covering  the  entire  laboratory  instruction  must  be  presented 
as  a  part  of  the  examination. 

Answer  three  questions  of  each  group,  and  one  additional  question  which  may  be 
selected  from  any  group. 

Group  I 

1.  (a)  Represent  the  cross-section  of  a  woody  stem  by  a  diagrammatic  figure. 

(b)  Label  the  various  parts  shown  and  give  the  function  or  functions 
of  each. 

2.  Describe  the  epidermis  and  the  green  tissue  of  a  typical  leaf,  giving  the  various 

functions  of  the  parts  described. 

3.  (a)  Name  and  describe  a  seed  with  endosperm,     (b)  Describe  the  germi- 

nation of  this  seed,  (c)  How  are  the  solid  foods  stored  up  in  a  seed 
made  available  for  the  young  plant  ? 

4.  Discuss  the  plants  of  deserts  and  of  forests  in  relation  to  their  environment. 

5.  (a)  How  do  leaves  maintain  their  rigidity  ?     (b)  Why  does  the  loss  of  water 

by  leaves  cause  them  to  wilt  ?  (c)  Why  does  a  piece  of  wood  remain 
rigid  when  dry  ? 

Group  II 

6.  (a)  Name  three  plants  in  which  motile  asexual  spores  are  found,     (b)  Name 

two  plants  in  which  non-motile  asexual  spores  are  found,  (c)  Assign 
each  of  the  plants  named  to  the  great  group  or  phylum  to  which  it 
belongs. 

7.  Name  a  liverwort  and  outline  its  life-history, 

8.  (c)  Distinguish  between  homospory  and  heterospory.     (b)  Name  a  homos- 

porous  plant;  a  heterosporous  plant,  (c)  Describe  briefly  the  game- 
tophytic  generation  of  the  heterosporous  plant  you  have  named. 

9.  (a)  Name  an  alga  in  which  the  sex  organs  are  differentiated,     (b)  Describe 

the  sex  organs  and  the  process  of  fertilization  in  the  plant  you  have 
named. 

10.  (c)  What  is  transpiration  ?     (b)  In  what  parts  of  the  plant  does  it  take  place  ? 

(c)  In  what  ways  may  transpiration  be  injurious  to  a  plant  ?  (d)  How 
may  excessive  transpiration  by  plants  be  prevented  ? 

Group  III 

11.  Discuss  the  various  ways  in  which  agricultural  field  crops  may  be  improved. 

12.  (a)  Name  two  vegetable  fibers  of  commercial  importance,     (b)  Show  how 

the  fibers  are  obtained  from  the  plants  producing  them,  (c)  What 
commercial  uses  are  made  of  the  fibers  you  have  named  ? 

13.  (a)  Give  the  names  of  two  vegetable  drugs  and  of  the  plants  from  which  they 

are  obtained,     (b)  Tell  briefly  how  the  drugs  named  are  extracted. 

14.  Name  three  edible  fungi,  and  show  how  they  can  be  recognized. 

15.  (a)  What  are  the  characteristics  of  bacteria?     (b)  Discuss  the  part  played 

by  bacteria  in  processes  of  decay. 

1 6 


1917 
BOTANY 

Friday  2  p.m.     Two  hours 

Answer  three  questions  of  each  group,  and  one  additional  question  which  may  be 
selected  from  any  group. 

Group  I 

1.  Make  a  drawing  of  one  cell  of  an  alga  and  label  all  the  parts. 

2.  Enumerate  the  differences  in  structure  between  a  woody  dicotyledonous 

stem  such  as  an  oak  and  a  monocotyledonous  stem  such  as  corn. 

3.  Compare  by  labeled  drawings  the  following  floral  t\^es:    (a)  hj-pogynous 

(superior)  and  epigynous  (inferior);  (b)  regular  and  irregular.  Give  the 
name  of  the  plant  used  to  illustrate  each. 

4.  (a)  Name  four  different  t^^pes  of  edible  fruits,     (b)  What  floral  parts  enter 

into  each  of  them  ? 

5.  (a)  In  what  different  parts  of  a  seed  may  its  food  supply  be  stored  ? 

(b)  Name  three  foods  found  in  seeds,  (c)  How  would  you  detect  the 
presence  of  each  experimentally  ? 

Group  II 

6.  Describe  fully  with  illustrations  the  life  history  and  life  processes  of  the 

yeast  plant. 

7.  (a)  Name  two  families  of  monocotyledons  and  three  families  of  dicotyledons. 

Gi\'e  a  representative  plant  of  each  family,  (b)  Give  one  characteristic 
by  reason  of  which  you  assign  each  plant  named  in  answer  to  (a)  to  its 
particular  family. 

8.  Explain  fully  what  is  meant  by  the  expression  "alternation  of  generations." 

In  what  group  of  plants  is  this  phenomenon  most  obvious  ? 

9.  (a)  Explain  the  use  of  the  terms:  species,  genus,  and  family  as  used  in  botany. 

(b)  Select  a  plant  known  to  you  and  give  its  scientific  name  and  the 
family  to  which  it  belongs. 

10.  Describe  the  process  of  photosynthesis,  indicating  (a)  the  substances  used, 

(b)  where  each  is  obtained,  (c)  how  each  is  obtained,  (d)  the  conditions 
necessary  for  carr\'ing  on  the  process,  and  (e)  the  substances  produced. 

Group  III 

11.  (2)  Name  four  plants  important  because  of  their  medicinal  value,     (b)  In 

what  part  or  parts  of  each  plant  does  the  medicinal  material  occur  ? 

12.  Give  a  brief  discussion  of  forests,  including  (a)  areas  of  greatest  density  in 

the  United  States,  (b)  uses  of  the  forests,  (c)  dangers  to  the  forests, 
(d)  methods  used  in  conserving  the  forests. 

13.  Describe  briefly  two  methods  by  which  plant  breeders  are  improving  plants. 

14.  Explain  three  ways  in  which  soils  may  be  impro^•ed  for  agricultural  purposes. 

15.  From  what  plant  and  from  what  part  of  the  plant  is  each  of  the  following 

food  and  textile  products  obtained:  cotton,  linen,  manila-hemp,  flour, 
tapioca,  cinnamon,  sugar,  and  coffee? 


1918 

BOTANY 

Friday,  June  21  2  p.m.     Two  hours 

Answer  three  questions  of  each  group,  and  one  additional  question  which  may  be 
selected  from  any  group. 

Group  I 

1.  The  plant  embryo:    (a)   Where  found?     (b)   Of  what  parts  composed? 

(c)  How  long  may  it  stay  in  a  dormant  condition?  (d)  What  are  the 
conditions  necessary  for  its  growth  ?  (e)  Where  is  its  food  supply  stored, 
and  how  is  it  rendered  available  for  the  growing  embryo  ? 

2.  How  do  monocotyledons  and  dicotyledons  differ :  (a)  In  the  external  appear- 

ance of  the  plant  ?  (b)  In  the  internal  structure  of  their  stems  ?  (c)  In 
their  leaf  structure  ?     (d)  In  their  floral  plan  ?     (e)  In  their  seed  structure  ? 

3.  Name  the  principal  ecological  groups  of  plants,  and  briefly  state  how  the 

structure  of  the  plants  of  each  group  is  fitted  for  the  special  environment. 

4.  Roots:  (a)  Describe  the  most  conspicuous  structural  features  and  the  manner 

of  growth  of  a  young  root,     (b)  Name  a  plant  which  has  aerial  roots. 

(c)  Name  and  describe  a  root  especially  fitted  for  storage,  (d)  Describe 
the  roots  of  a  parasite,     (e)  What  is  a  mycorrhiza  ? 

5.  (a)  What  is  a  gametophyte  ?     (b)  What  is  a  sporophyte  ?     (c)  Name  a  plant 

which  has  the  gametophyte  more  highly  developed  than  the  sporophyte. 

(d)  Name  a  plant  which  has  the  sporophyte  dependent  upon  the  gameto- 
phyte. (e)  Name  a  plant  which  has  the  sporophyte  more  highly  developed 
than  the  gametophyte. 

Group  II 

6.  (a)  Give  the  distinctive  features  of  the  following  plant  famihes:    (1)  Pulse 

(Leguminosae),  (2)  Grass  (Gramineae),  (3)  Nightshade  (Solanaceae), 
(4)  Mustard  (Cruciferae),  (5)  Rose  (Rosaceae),  (b)  Name  two  food-plants 
of  each  of  these  five  families. 

7.  Explain  the  exact  part  which  water  plays  in:   (a)  germination,   (b)  food 

manufacture,  (c)  growth,  (d)  movement,  (e)  maintenance  of  rigidity. 

8.  State  how  you  would  demonstrate  the  following  facts  giving  clearly  the 

essential  points  of  your  method,  but  not  all  the  details:  (a)  carbon  dioxide 
is  a  product  of  plant  respiration;  (b)  germinating  barley  seeds  contain 
diastase;  (c)  stomata  are  more  abundant  on  the  under  side  of  most  leaves 
than  on  the  upper  side;    (d)  plants  require  nitrates  for  their  growth; 

(e)  beans  contain  protein. 

9.  A  bean  seed  was  planted  in  May;   from  this  seed  a  vigorous  plant  developed 

and  reached  full  maturity  before  it  was  killed  by  frost  in  October.  State 
the  most  important  periods  of  development  and  the  chief  events  in  the 
life  of  this  plant,  noting  what  organs  were  most  conspicuous  at  each  period. 

10.  (a)  Give  the  distinctive  features  of  the  following  groups  of  fungi:  (1)  yeasts, 
(2)  molds,  (3)  sac-fungi,  (4)  mildews,  (5)  mushrooms.  (6)  State  briefly 
why  each  group  is  important  economically. 

(SEE  NEXT  PAGE) 
i8 


Group  III 

11.  What  would  be  the  necessary  steps  in  the  process  of  producing  a  hybrid 

fruit  ? 

12.  (a)  Which  of  the  algae  may  be  the  cause  of  the  disagreeable  odor  and  taste 

of  reservoir  water  ?  How  can  this  condition  be  remedied  ?  (b)  Why 
are  the  diatoms  an  interesting  and  important  group  ?  (c)  What  use  is 
made  of  kelps  at  the  present  time  ? 

13.  Explain  how  in  improving  wheat  or  any  other  crop,  by  selection  or  breeding, 

(a)  the  demands  of  the  market,  (b)  the  farm  or  home  needs,  and  (c)  the 
climatic  conditions  must  be  considered. 

14.  (a)  What  is  cellulose  ?     (b)  Name  a  substance  which  is  almost  pure  cellulose. 

(c)  What  articles  of  commerce  are  made  from  cellulose  ?  (d)  Which  of 
our  foods  contain  a  great  deal  of  cellulose  ? 

15.  What  is  the  United  States  government  doing:   (a)  to  conserve  our  forests; 

(b)  to  introduce  new  kinds  of  plants;  (c)  to  control  the  spread  of  plant 
diseases  ? 


>9 


Page  1 

1919 

BOTANY 

Friday,  June  20  2  p.m.    Two  hours 

Answer  three  questions  of  each  group  and  one  additional  question  which  may  be 
selected  from  any  group.  Candidates  are  advised  to  apportion  the  time  wisely  among 
the  ten  questions.     Nimiber  each  answer  to  correspond  with  the  question  selected. 

Group  I 

1.  State  in  regard  to  protoplasm:   (a)  its  appearance,  (b)  its  chemical  composi- 

tion, (c)  its  activities,  (d)  where  it  occurs.  Make  a  fully  labeled  diagram 
of  a  typical  cell. 

2.  Describe  five  different  t>'pes  of  leaves  and  show  how  each  is  fitted  for  its 

special  environment  or  function. 

3.  What  is  a  fruit  ?    Name  definite  examples  of  the  following  kinds  of  fruit : 

(a)  a  unipistillary,  dry,  dehiscent  fruit;  (b)  a  unipistillary,  fleshy  fruit; 
(c)  a  fruit  formed  from  several  pistils  of  one  flower;  (d)  a  fruit  composed 
of  several  carpels;  (e)  a  fruit  formed  from  the  pistils  of  several  flowers. 

4.  As  an  example  of  your  best  scientific  drawing  and  labeling  illustrate  one 

of  the  following:  (a)  two  types  of  flowers  which  have  special  adaptations 
for  insect  pollination;  (b)  a  fern  sporophyll  and  an  enlarged  sporangium 
containing  spores;  (c)  archegonium  of  a  moss  plant  as  seen  in  longitudinal 
section;    (d)  cross-section  of  a  typical  leaf. 

5.  State  where  the  following  structures  occur  and  give  their  function:   (a)  lenti- 

cels,  (b)  stipules,  (c)  basidiospores,  (d)  asci,  (e)  endosperm. 

Group  II 

6.  State  fully  how  you  proved  by  experiments  that  more  than  one  factor  is 

involved  in  photosynthesis. 

7.  State  how  you  would  demonstrate  experimentally:  (a)  the  presence  of  oxygen 

as  essential  to  growth;  (b)  the  presence  of  starch;  (c)  the  presence  of 
mineral  matter;  (d)  the  transfer  of  water  through  ducts;  (e)  the  presence 
of  diastase  in  malt. 

8.  (a)  Define  osmosis,     (b)  How  would  you  demonstrate  it  experimentaUy  ? 

(c)  How  are  the  conditions  for  osmosis  fulfilled  in  the  root  hair  ?  (d)  Where 
else  in  plants  does  osmosis  occur  ?     (e)  What  is  plasmolysis  ? 

9.  State  briefly  the  life-history  of  two  of  the  following  plants:  (a)  White-pine 

blight,  (b)  a  fern,  (c)  Fucus,  (d)  a  beet  plant,  (e)  a  typical  mold. 

10.  Name  the  most  distinctive  features  which  would  enable  you  to  identify  the 
following:  (a)  a  lichen,  (b)  a  pine,  (c)  a  liverwort,  (d)  a  member  of  the 
mint  family,  (e)  a  horsetail,  (/)  a  monocotyledonous  plant,  (fi)  an  oak, 
(h)  a  cactus,  (i)  a  member  of  the  pulse  family,  (j)  the  sporophyte  of  a  moss 
plant. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

Group  III 

11.  Name  five  important  crops  of  your  state.     Tell  what  has  been  done  to  im- 

prove each  crop. 

12.  (a)  What  chemical  compounds  are  found  in  a  good  commercial  fertilizer  for 

general  garden  or  farm  use?     (b)  Explain  the  role  of  bacteria  in  soils. 

(c)  What  weeds  indicate  the  need  of  liming  the  soil  ?  (d)  Why  is  rotation 
of  crops  advisable  ?  (e)  When  should  fruit  trees  be  pruned  and  why  at 
the  time  specified  ? 

13.  (a)  Name  two  industries  which  make  use  of  plant  enzymes,     (b)  Name 

two  plants  which  furnish  edible  leaves,     (c)  Name  two  medicinal  seeds. 

(d)  Name  two  plants  which  furnish  rope  fibers,  (e)  Name  two  plants 
which  have  useful  latex. 

14.  (a)  Name  four  valuable  forest  trees,  stating  what  constitutes  their  special 

value.  (6)  Name  four  trees  used  for  street  planting,  giving  their  good  and 
bad  points. 

15.  Write  a  clear,  well-arranged  topical  outline,  giving  at  least  three  main  topics 

and  several  subtopics  under  each  main  topic,  on  one  of  the  following  sub- 
jects: (a)  the  importance  of  the  Department  of  Agriculture;  (6)  the  making 
of  new  varieties  of  plants;  (c)  seed  dispersal;  (d)  parasitic  plants;  (e)  rela- 
tions between  plants  and  animals. 


Page  1 

1920 

BOTANY 

Friday,  June  25  2  p.m.    Two  hours 

Answer  three  questions  of  each  group  and  one  additional  question  which  may  be 
selected  from  any  group.  Candidates  are  advised  to  apportion  the  time  wisely  among  the 
ten  questions  answered.    Number  each  answer  to  correspond  with  the  question  selected. 

Group  I 

1.  a)  Trace  the  course  of  the  fibrovascular  bundles  throughout  an  entire  plant. 

b)  Of  what  parts  is  the  bundle  composed  ? 

c)  WTiat  is  the  use  of  each  part  ? 

d)  Of  what  is  the  heart-wood  of  a  tree  composed  ? 

e)  Of  what  use  are  the  medullary  rays  ? 

2.  Describe  a  cell  in  a  growing  region  of  a  plant.     Make  a  properly  labeled 

drawing  of  it.     How  may  it  be  changed  to  make  it  a  conducting  cell  ? 
A  storage  cell  ?     A  supporting  cell  ? 

3.  a)  When  a  branch  increases  in  size  from  one  foot  in  length  and  a  half-inch 

in  diameter  to  five  times  these  dimensions,  what  two  types  of  growth 
have  occurred  ? 
b)  What  external  markings  or  features  may  be  observed  during  the  winter 
on  a  five-year-old  branch  ? 

4.  a)  Name  a  definite  flower  and  describe  its  pistil,  mentioning  all  the  external 

and  internal  structures  of  the  pistil  which  can  readily  be  distinguished. 
State  what  the  permanent  parts  of  the  flower  develop  into  later. 
b)  State  the  function  of  the  following  structures:    (i)  calyx,  (ii)  anther. 
(iii)  receptacle,  (iv)  pollen,  (v)  corolla. 

5.  Briefly  describe  the  following  structures: 

a)  The  sporophyte  of  a  moss  plant. 

b)  The  reproductive  organs  of  a  mold. 

c)  The  prothallus  of  a  fern. 

d)  The  thallus  of  a  liverwort. 

e)  The  male  flower  of  a  pine  tree. 


Group  II 

6.  Discuss  chlorophyll,  stating:  (a)  in  what  form  and  in  what  different  plant 
organs  it  occurs;  (b)  the  conditions  necessary  for  its  formation  and  activ- 
ity; (c)  its  work  in  the  plant;  (d)  how  it  may  be  extracted  from  plants; 
(e)  what  are  the  habits  of  plants  that  have  no  chlorophyll. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

7.  a)  If  seedlings  are  grown  in  a  water  culture,  what  chemical  compounds 

should  the  water  contain  to  be  a  perfect  nutrient  solution  ? 

b)  What  chemical  changes  occur  in  a  seed  during  germination  ? 

c)  Why  is  clover  planted  to  improve  the  soil  for  later  crops  ? 

d)  When  fresh-water  plants  are  placed  in  salt  water,  and  salt-water  plants 

put  in  fresh  water,  what  changes  occur  in  the  cells  of  each  ?    Explain 
why  these  changes  occur. 

e)  Give  a  chemical  test  for  sugar. 

8.  Explain  the  relation  of  transpiration  in  the  following  instances:   (a)  Fall  of 

leaves;   (b)  Adaptations  in  desert  plants;   (c)  Distribution  and  position  of 
leaf  stomata;   (d)  Protection  of  winter  buds;   (e)  Wilting  of  plants. 

9.  a)  Explain  the  reasons  for  the  following  contrasted  groups  in  the  classilication 

of    plants:      (i)     Gymnosperm — Angiosperm,     (ii)     Monocotyledon — 
Dicotyledon,    (iii)    Annual — Perennial,    (iv)    Monoecious — Dioecious, 
(v)  Polypetalous — Apetalous. 
b)  Name  a  plant  which  is  an  example  of  each  of  these  ten  classes. 

10.  Name  and  briefly  describe  a  representative  of  the  following  groups  of  plants: 

(a)  a  fern,  (b)  a  blue-green  alga,  (c)  a  lichen,  (d)  a  palm,  (e)  a  mushroom. 

Group  III 

11.  Name  five  common  weeds.     State  how  you  would  identify  each.     Describe 

the  seed  dispersal  of  two  especially  successful  weeds.     Name  two  weeds 
that  have  other  methods  of  propagation  and  describe  the  methods. 

12.  a)  State  upon  what  substances,  and  under  what  conditions,  colonies  of 

bacteria  may  be  grown  most  favorably  for  examination. 
b)  Discuss  bacteria  in  relation  to  dairy  products. 

13.  Name  five  new  uses  of  plants,  or  plant  products,  called  forth  by  the  war. 

State  the  part  or  parts  of  the  plant  used  in  securing  these  products. 

14.  What  measures  are  being  taken  to  control  the  spread  of  the  following  plant 

diseases:   (a)  White  pine  blight,  (b)  potato  wart,  (c)  wheat  rust,  (</)  the 
smuts  on  oats,  wheat,  corn,  and  barley,  (e)  the  grape  mildew. 

15.  Name  two  useful  plants  of  each  of  the  five  following  families  of  plants,  and 

state  for  what  purpose  each  of  the  ten  plants  is  used:    (a)  Grass  family, 

(b)  Solanum  or  Nightshade  family,  (c)  Spurge  family,  (d)  Rose  family, 
(e)  Parsley  family. 


23 


M^ 


CHEMISTRY 


25 


1916 
CHEMISTRY 

Friday  9 :  00  a.m.     Two  hours 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  a 
part  of  the  examination. 

Answer  nine  questions  as  indicated  below.  No  extra  credit  will  be  given  for  more 
than  nine  questions. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Part  I 
(Answer  all  questions  in  this  group.     Each  question  counts  12.) 

1.  Write  equations  for  the  following  reactions,  using  formulas  throughout.     To 

receive  credit,  the  equations  must  be  absolutely  correct, 

(a)  Silver  nitrate+ ferric  chloride  = 

{h)  Sodium  carbonate+ nitric  acid  = 

(c)  Ammonium  chloride+ calcium  hydroxide  = 

{d)  Zinc  hydroxide+ hydrochloric  acid  = 

{e)  Combustion  of  phosphorus  in  air  = 

(/■)  Silver  chloride-f  zinc= 

2.  (a)  Describe  in  detail  how  you  should  determine  experimentally  either 

(1)  the  hydrogen  equivalent  of  some  metal,  or  (2)  the  weight  of  a  liter 
of  some  gas. 
{b)  What  is  meant  by  the  relative  activity  of  the  metallic  elements  ?  Arrange 
in  order  of  decreasing  activity  the  following:  gold,  hydrogen,  zinc, 
sodium,  copper.  (The  arrangement  must  be  correct  throughout  to 
receive  credit.) 

3.  (a)  Name  each  of  the  following  compounds:    the  potassium  salt  of  chlor- 

platinic  acid,  the  sodium  salt  of  tellurous  acid,  a  compound  containing 

magnesium  and  silicon  only,  the  salt  obtained  by  replacing  half  the 

hydrogen  of  carbonic  acid  with  sodium. 
{b)  If  the  percentages  of  calcium  in  two  samples  of  limestone  are  40  per  cent 

and  38  per  cent  respectively,  what  conclusion  should  you  draw  in 

regard  to  the  specimens  ?    State  the  law  upon  which  your  conclusion 

is  based.     (Atomic  weights:  Ca  40,  O  16,  C  12.) 
(c)   A  body  of  air  at  constant  pressure  occupies  a  volume  of  500  c.c.  at  20°  C. 

At  what  temperature  will  its  volume  become  1,000  c.c.  ? 

4.  How  should  you  proceed  to  produce  the  first-mentioned  substance  from  the 

second  in  four  of  the  following  cases  ?    Describe  each  step  in  the  process. 
(a)  Nitrogen  from  the  atmosphere; 
{b)  Kerosene  from  crude  petroleum; 
(c)   Sulphuric  acid  from  sulphur; 
{d)  Lime  water  from  marble; 
(e)  Hydrochloric  acid  from  sulphuric  acid. 

5.  (a)  How  many  grams  of  water  of  crystallization  are  there  in  the  crystallized 

barium  chloride  (BaCl2  •  2H2O)  obtained  from  10  grams  of  barium  ? 
(Atomic  weights:  Ba  137,  CI  35.  5,  O  16,  H  1.) 
{b)  How  many  cubic  centimeters  of  ammonia  gas,  NH3,  under  standard 
conditions,  can  be  obtained  from  5.00  grams  of  ammonium  phos- 
phate, (NH4)3P04,  by  treating  it  with  sodium  hydroxide  in  excess? 
(NHj3P04+3NaOH  =  Na3PO,+3H20-}-3NH3.  (Atomic  weights: 
P  31,  Na  23, 0  10,  N 14,  H  1 .)     One  liter  of  ammonia  weighs  0 .  77  gram. 

(SEE  NEXT  PAGE) 
26 


Part  II 

(Omit  one  group.     Each  question  counts  10.) 

Group  A 

6.  Answer  five  of  the  following:    {a)  How  would  you  make  ferrous  chloride 

from  ferric  chloride  ?  {b)  Ferric  chloride  from  ferrous  chloride  ?  (c)  White 
lead  from  lead  ?  {d)  Sodium  sulphite  from  sodium  hydroxide  ?  (e)  Sodium 
hypochlorite  from  sodium  hydroxide  ?  (/)  Alum  crystals  from  aluminum 
sulphate  ? 

7.  Mention  very  briefly  any  means  of  identifying  with  certainty  each  of  the 

following  gases:  hydrogen,  nitrogen,  carbon  dioxide,  sulphur  dioxide,  nitrous 
oxide,  chlorine,  carbon  monoxide,  hydrogen  sulphide,  oxygen,  ozone. 

Group  B 

8.  (a)  Ten  liters  of  a  gas  whose  formula  is  C2H6O  are  completely  burned  in 

oxygen.  How  many  liters  of  oxygen  gas  are  required  for  its  complete 
combustion  ?  How  many  liters  of  carbon  dioxide  should  result  ?  All 
volumes  are  measured  under  the  same  conditions  of  temperature  and 
pressure. 
{h)  If  the  temperature  of  a  gas  enclosed  at  an  initial  pressure  of  one  atmos- 
phere is  decreased  from  37°  C.  to  27°  C.  without  change  in  volume, 
what  will  be  the  final  value  of  the  pressure  ? 

9.  (a)  What  classes  of  substances  are  electroly tically  dissociated  ?    What  is  the 

effect  of  dilution  on  the  degree  of  dissociation  of  the  substance  ?     How 
may  the  degree  of  dissociation  be  diminished  without  changing  mate- 
rially the  volume  of  the  solution  ? 
{b)  Show  how  the  electric  current  is  conveyed  through  a  solution  of  CUSO4, 
and  indicate  the  reactions  that  take  place  at  the  poles. 

Group  C 

10.  (a)  Mention  one  important  industrial  process  depending  on  each  of  the 

following  phenomena  respectively:    reduction,  catalysis,  crystalliza- 
tion, electrolysis. 
(6)  State  what  impurities  render  water  unfit  for   (1)   drinking  purposes, 
(2)  steam  boilers,  (3)  laundries;    and   outline   a  different   practical 
method  adapted  to  improving  the  water  in  each  case. 

11.  Answer  four  of  the  following  questions: 

(a)  Explain  the  cleansing  action  of  soaps.     Of  what  substances  are  washing 

powders  likely  to  be  composed  ? 
{b)  Describe  one  method  of  converting  pig  iron  into  steel, 
(c)   Explain  upon  a  chemical  basis  the  use  of  ozone  in  the  purification  of  water. 
{d)  Name  two  products  of  commercial  importance  that  can  be  obtained,  by 

chemical  change,  from  starch. 
ie)  W^hat  role  does  each  of  the  three  general  classes  of  foods  play  in  nutrition  ? 


27 


1917 
CHEMISTRY 

Friday  2  p.m.    Two  hours 

Answer  nine  questions  as  indicated  below.     No  extra  credit  will  be  given  for  more 
than  nine  questions. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Part  I 
(Answer  all  questions  in  this  group.     Each  question  counts  12.) 

1.  Write  equations  for  the  following  reactions,  using  formulas  throughout.     To 

receive  credit,  the  equations  must  be  absolutely  correct. 

(a)  Sodium  acid  carbonate+sulphuric  acid  = 

ijb)  Carbon  dioxide + heated  carbon  = 

(c)  Silver  sulphate + barium  chloride  = 

{d)  Copper+hot  concentrated  sulphuric  acid= 

(e)  Hydrogen  sulphide  burned  in  excess  of  air  = 

(/)  Potassium  chlorate  heated  with  manganese  dioxide  = 

2.  Select  three  of  the  substances:  chlorine,  potassium  nitrate,  zinc,  slaked  lime, 

and  give  the  following  information  in  regard  to  each:  (a)  Name  a  naturally 
occurring  material  from  which  the  substance  is  commonly  made,  {b) 
Write  the  equation  or  equations  representing  the  preparation  of  the  sub- 
stance from  this  material,     (c)  Give  one  important  commercial  use. 

3.  (a)  Given  a  soluble  oxide,  how  could  you  determine  whether  or  not  it  was 

the  oxide  of  a  metal  ? 
iJb)  What   three    tests   could   you   make   to   distinguish   between   sodium 

chloride  and  finely  divided  parafl&n  ? 
(c)  Define  the  term  "radical,"  and  illustrate  by  an  example. 
{d)  Illustrate  the  law  of  multiple  proportions  by  considering  the  composition 

by  weight  of  two  compounds  containing  the  same  elements. 

4.  (a)  What  forms  of  energy  are  manifest  when  a  mixture  of  hydrogen  and 

oxygen  is  exploded?  From  what  source  are  these  forms  of  energy 
derived  ?  Apply  the  law  of  conservation  of  energy  to  this  reaction. 
{b)  Excess  of  phosphorus  is  allowed  to  act  on  air  at  atmospheric  pressure  in  a 
sealed  flask.  When  the  reaction  is  complete,  (1)  What  is  the  pressure 
(approximately)  in  the  flask,  the  temperature  remaining  the  same? 
(2)  How  does  the  weight  of  the  flask  and  contents  after  the  reaction 
compare  with  the  weight  before  ?  State  the  law  upon  which  the  latter 
conclusion  is  based. 

5.  (a)  If  50 .0  grams  of  calcium  carbonate,  CaCOs,  are  added  to  50.0  grams  of 

hydrochloric  acid,  HCl,  in  water  solution;  which  substance  remains 
in  excess?  What  is  the  weight  of  this  excess?  (Atomic  weights: 
Ca  40,  CI  35.5,  O  16,  C12,  H  1.) 

(SEE  NEXT  PAGE) 


(b)  What  volume  of  nitric  oxide,  NO,  measured  under  standard  conditions, 

can  be  obtained  by  adding  10.0  grams  of  copper  to  excess  of  dilute 
nitric  acid  according  to  the  equation : 

3CU+8HNO3 =3Cu(N03)2+4H20+2NO  ? 

(Atomic  weights:  Cu  64,  O  16,  N  14,  H  1.     One  liter  of  nitric  oxide  at  0°  C. 
and  760  mm.  weighs  1 .34  grams.) 

Part  II 
(Omit  one  group.     Each  question  counts  10.) 

Group  A 

6.  Answer  five  parts  of  this  question.     How  could  you  demonstrate  experi- 

mentally that:  {a)  Nitric  acid  is  an  oxidizing  agent  ?  {b)  Sulphur  dioxide 
is  a  reducing  agent  ?  (c)  Copper  sulphate  is  a  salt  ?  {d)  Alcohol  contains 
carbon?     (e)  Kerosene  is  a  mixture?     (/)  Litharge  contains  lead? 

7.  How  could  you  make:    (a)  Zinc  sulphate  from  zinc  chloride?     {b)  Copper 

from  copper  sulphate  ?  [c)  Ferric  oxide  from  ferric  chloride  ?  {d)  Sodium 
sulphite  solution  from  sulphur  ? 

Group  B 

8.  {a)  What  is  meant  by  the  term  "reversible  reaction"? 

ib)  Under  what  three  conditions  will  a  reaction  proceed  to  completion  ? 

(c)  Illustrate  each  of  these  conditions  separately  by  writing  the  equation 

of  a  suitable  reaction,  showing  which  condition  is  fulfilled  in  each  case. 

9.  (a)  State  Gay-Lussac's  law  of  combining  volumes.     What  volume  of  oxygen 

is  required  for  the  complete  combustion  of  five  liters  of  acetylene, 
C2H2?  All  measurements  are  to  be  made  under  the  same  conditions 
of  temperature  and  pressure. 
(6)  One  liter  of  gas  A  weighs  1 .  98  grams.  One  liter  of  gas  B  weighs  0 .  77 
gram,  under  the  same  conditions.  The  molecular  weight  of  A  is  44. 
What  is  the  molecular  weight  of  B  ? 

Group  C 

10.  (a)  Describe  the  electrolytic  process  for  silver  plating. 

{b)  Of  what  chemical  elements  are  ordinary  fuels  composed?  What  pro- 
ducts are  formed  by  their  combustion  ?  Aside  from  expense,  what  are 
the  disadvantages  of  sulphur  as  a  fuel  ? 

11.  (a)  Show  briefly  the  relation  of  four  constituents  of  the  atmosphere  to  the 

vital  processes  of  plants  and  of  animals. 
{b)  Describe  the  chemical  changes  that  occur  in  a  blast-furnace  for  making 
pig-iron  from  an  ore  consisting  of  ferric  oxide  and  sand. 

-9 


1918 
CHEMISTRY 

Friday,  June  21  2  p.m.    Two  hours 

Answer  nine  questions  as  indicated  below.    No  extra  credit  will  be  given  for  more 
than  nine  questions.  > 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper.       p^ 


Part  I 

{Answer  all  questions  in  this  part.     Each  question  counts  12.) 

1.  Write  equations  for  the  following  reactions,  using  formulas  throughout.    The 

equations  must  be  correct  in  every  particular. 

(a)  Ammonium  nitrate  (heated)  = 

{b)  Ferric  chloride + zinc = 

(c)  Methane  (marsh  gas)+oxygen  (ignited)  = 

{d)  Hydrogen  sulphide+ silver  nitrate  = 

(e)  Copper  oxide  (heated) + hydrogen  = 

(/)  Calcium  oxide+sodium  carbonate + water = 

2.  How  would  you  prove,  by  chemical  means,  the  presence  (a)  of  carbon  mon- 

oxide if  mixed  with  sulphur  dioxide  ?  {b)  of  hydrogen  if  mixed  with  dry 
air  (if  the  amount  of  hydrogen  is  too  small  to  make  the  mixture  explosive)  ? 
(c)  of  gold  in  copper  ?  {d)  of  sulphuric  acid  in  a  solution  of  hydrochloric 
acid? 

3.  (a)  What  is    the    percentage   of    ammonia    in    cuprammonium    sulphate, 

CuS04-4NH3-H20  ?    (Atomic  weights:  Cu  64,  S  32, 0  16,  N  14,  H  1.) 

(6)  What  weight  of  pure  sodium  bicarbonate,  NaHCOa,  must  be  treated  with 
excess  of  acid  to  produce  250  liters  of  carbon  dioxide  measured  at  0°  C. 
and  1520  mm.  pressure?  (Atomic  weights:  Na  23,  O  16,  C  12,  H  1. 
One  liter  of  carbon  dioxide  at  0°  C.  and  760  mm.  weighs  1 .98  grams.) 

4.  (o)  Given  the  valence  of  A  as  three,  derive  the  probable  valences  of  B,  C,  and 

D  from  the  following  formulas:  A2B3,  B2C,  B5D2.     What  would  be  the 
formula  of  a  compound  of  A  with  C  ? 

{b)  Prove  that  the  law  of  definite  proportions  is  a  necessary  consequence  of 
the  atomic  theory; 

5.  Describe  a  method  for  the  preparation  of  three  of  the  following  substances: 

(a)  sodium,  {b)  nitric  acid,  (c)  hydrogen  sulphide,  {d)  calcium  carbonate. 
How  would  you  separate  the  desired  product,  in  each  case,  from  the  reaction 
mixture  ? 

30  (SEE  NEXT  PAGE) 


Part  II 
(Omit  one  group.    Each  question  counts  10.) 
Group  A 

6.  Arrange  three  metals  in  the  order  of  decreasing  activity.  Describe  in  detail 
three  experimental  methods  by  which  the  correctness  of  the  suggested  order 
may  be  proved. 

J.  (a)  State  the  physical  and  chemical  characteristics  of  chlorine,  bromine,  and 
iodine  as  regards:  physical  state,  color,  solubility,  tendency  to  combine 
with  hydrogen. 

(b)  How  may  bleaching  powder  be  made  ?    What  are  its  properties  ? 

Group  B 

8.  (a)  What  weight  of  sulphur  dioxide  will  occupy  a  volume  equal  to  that  of 

42  grams  of  nitrogen  at  the  same  temperature  and  pressure  ?  (Atomic 
weights:   S32,  016,  N14.) 

(6)  What  volume  of  a  solution  of  hydrochloric  acid  containing  73  grams  per 
liter  would  suffice  for  the  exact  neutralization  of  the  sodium  hydroxide 
obtained  by  allowing  0 .  46  gram  of  metallic  sodium  to  act  upon  water  ? 
(Atomic  weights:  CI  35.5,  Na  23,  O  16,  H  1.) 

9.  {a)  What  is  a  reversible  reaction  ?    Illustrate  by  means  of  an  equation. 
{h)  Under  what  three  conditions  will  a  reaction  go  to  completion  ? 

(c)  On  the  basis  of  the  electrolytic  dissociation  theory,  how  would  you 

explain  (1)  the  neutralization  of  an  acid  by  a  base?  (2)  the  changes 
that  take  place  when  a  solution  of  copper  sulphate  is  electrolyzed 
between  copper  electrodes  ? 

Group  C 

10.  {a)  What  substance  burns  with  a  blue  flame  on  the  top  of  a  coal  fire  ?    Write 

two  equations  for  the  reactions  involved  in  the  formation  of  this  sub- 
stance; write  an  equation  for  the  reaction  involved  in  its  combustion. 

(6)  Define  the  term  "by-product."  Show  how  a  valuable  by-product  is 
obtained  in  some  chemical  process  of  commercial  importance. 

11.  Considering  each  of  the  following  substances  separately,  name  two  impor- 

tant products  made  from  it  directly  or  by  admixture  or  reaction  with  other 
substances:   (a)  lime,  {b)  salt,  (c)  crude  petroleum,  {d)  coke,  {e)  sand. 


3* 


Page  1 

1919 
CHEMISTRY 

Friday,  June  20  2  p.m.    Two  hours 

Answer  nine  questions  as  indicated  below.    No  extra  credit  will  be  given  for  more 
than  nine  questions. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 


* 


Part  I 

(Answer  all  questions  in  this  part.    Each  question  counts  12.) 

1.  Describe  a  method  for  the  laboratory  preparation  of  three  of  the  following 

substances:  (a)  sodium  nitrate,  {b)  ethyl  alcohol,  (c)  barium  sulphate, 
{d)  hydrochloric  acid.  WTiat  property  has  the  desired  product  in  each 
case  which  makes  it  possible  to  separate  it  ? 

2.  Write  equations  for  the  following  reactions,  using  formulas  throughout.     To 

receive  credit,  the  equations  must  be  correct  in  every  particular. 

(a)  Chlorine  (gas) + hydrogen  (gas)  = 

{h)  Sodium  carbonate + carbon  dioxide +water  = 

(c)  Ammonium  carbonate+ copper  (cupric)  chloride  = 

{d)  Ferric  oxide+ carbon  (heated)  = 

{e)  Ammonia  completely  burned  in  oxygen  = 

(/)  Silver  sulphate4-zinc  = 

3.  (a)  How  many  grams  of  sodium  hydroxide  will  be  required  to  neutralize 

9 . 8  grams  of  sulphuric  acid  ?  Name  the  products  formed  and 
determine  the  weight  of  each  product.  (Atomic  weights:  H  1,  O  16, 
Na  23,  S  32.) 

ih)  What  volume  will  one  Hter  of  gas  at  136.5°  absolute  have  at  136.5°  C, 
pressure  remaining  the  same  ? 

4.  How  could  you  show  ex'perimentally  that — 

(a)  fused  calcium  chloride  is  a  deUquescent  substance  ? 

{b)  carbonic  acid  is  unstable  ? 

(c)  nitric  acid  is  an  oxidizing  agent  ? 

{d)  diamond  is  a  form  of  carbon  ? 

{e)  sugar  is  not  an  electrolyte  ? 

(/)  a  hydrocarbon  contains  hydrogen  ? 

5.  (a)  Show  by  formulas  how  an  anhydride  is  related  to  the  corresponding  acid 

or  base. 

{b)  Suggest,  by  writing  appropriate  equations,  four  different  methods  for 

making  calcium  sulphate  from  calcium,  oxygen,  sulphur  trioxide,  and  1^ 

water. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 
32 


Page  2 

Part  II 
{Omit  one  group.     Each  question  counts  10.) 

Group  A 

6  (a)  Outline  a  method  by  which  pure  silver  nitrate  could  be  obtained  from  a 
silver  coin.  What  other  metal  is  present  in  the  coin,  and  how  may  it 
be  identified  ? 

{b)  Give  a  method  for  the  preparation  of  chlorine  from  common  salt. 

7.  (c)  Name   two   metals,   each   of    which   yields   two   oxides,  and   give   the 

formulas  of  the  oxides. 

{b)  Mention  two  elements  that  occur  in  allotropic  forms,  and  name  several 
allotropic  forms  in  each  case. 

(c)  Mention  three  metals  fusible  below  red  heat,  and  three  fusible  only  above 
red  heat. 

id)  Mention  three  gases  which  are  easily  liquefied,  and  three  which  are 
licjuefied  with  difficulty. 

{e)  Name  an  acid  all  of  whose  normal  salts  are  soluble  in  water. 

Group  B 

8.  (a)  Apply  Avogadro's  law  in  finding  the  volume  of  carbon  dioxide  formed 

from  the  burning  of  4  liters  of  carbon  monoxide  in  oxygen,  provided  all 
of  the  gases  are  measured  at  the  same  temperature  and  pressure. 
{b)  Name  the  components  in  a  water  solution  of  ammonia. 

9.  (a)  Write  an  equation  illustrating  a  reaction  between  two  salts  in  solution, 

which  does  not  go  to  completion.     Explain  why  this  reaction  does  not 
go  to  completion. 

{b)  How  does  a  water  solution  of  copper  sulphate  react  with  Htmus? 
Explain. 

Group  C 

10.  (a)  Explain  the  use  of  cream  of  tartar  in  baking  powders. 

(6)  When  a  compressed  mixture  of  air  with  gasoline  is  exploded  in  a  confined 
space,  what  substances  may  be  formed?  What  difference  in  the 
nature  and  relative  amounts  of  the  products  may  be  expected  (1)  if 
the  amount  of  gasoline  is  small  in  comparison  with  the  air  present  ? 
(2)  if  the  proportion  of  gasoline  is  unduly  large  ? 

11.  (a)  State  what  you  would  do  in  each  of  the  following  emergencies  respectively: 

(1)  Chlorine  inhaled. 

(2)  Acid  in  the  eye. 

(3)  Oil  burning  on  the  floor  or  desk. 

{b)  Distinguish  between  destructive,  fractional,  and  ordinary  distillation  by 
giving  a  practical  example  of  each. 

2>Z 


Page  1 

1920 
CHEMISTRY 

Friday,  June  25  2  p.m.    Two  hours 

Answer  nine  questions  as  indicated  below.     No  extra  credit  will  be  given  for  more 
than  nine  questions. 

Number  and  letter  your  answers  to  correspond  to  the  questions  selected. 


Part  I 
(Answer  all  questions  in  this  part.    Each  question  counts  12.) 

1.  Describe  a  method  for  the  laboratory  preparation  of  the  following  substances: 

(a)  sodium  chloride,  {h)  calcium  carbonate,  (c)  nitric  oxide.  What 
property  has  sodiimi  chloride  which  makes  it  possible  to  separate  it? 
calcium  carbonate  ?  nitric  oxide  ? 

2.  Illustrate  by  equations  the  action  of  dilute  sulphuric  acid  on  (a)  zinc,  {b)  cal- 

cium oxide,  (c)  ammonium  hydroxide,  {d)  sodium  carbonate,  {e)  ferrous 
sulphide,  (/)  barium  chloride.  Name  the  type  of  reaction  which  occurs  in 
each  case.  Formulas  must  be  used  throughout  and  the  equations  properly 
balanced  to  receive  credit. 

3.  Describe  an  experiment  illustrating  the  quantitative  character  of  chemical 

action,  including  apparatus,  method,  and  precautions.  Show  how  the 
data  found  in  the  experiment  warrant  the  conclusion  reached  The  data 
may  be  represented  by  letters. 

4.  If  540  grams  of  silver  react  with  an  excess  of  concentrated  sulphuric  acid 

according  to  the  equation  2  Ag+2  H2S04  =  Ag2S04+2  H2O+SO2,  what 
weight  of  silver  sulphate,  and  what  volume  of  sulphur  dioxide  measured 
under  standard  conditions  of  temperature  and  pressure,  will  be  formed? 
(Ag  108,  8  32,016,  HI.) 

Note. — One  liter  of  sulphur  dioxide  at  0°  C.  and  760  mm.  weighs  2.9  grams. 

5.  (c)  Which  contains  the  more  energy  under  the  same  conditions  of  tempera- 

ture and  pressure,  a  mixture  of  1  gram  of  hydrogen  and  8  grams  of 
oxygen  or  9  grams  of  water  ?     Give  the  reason  for  your  conclusion. 

{h)  Name  two  elements  having  more  than  one  valence.  Illustrate  each  of 
the  valences  of  these  elements  by  constructing  a  formula  containing 
also  one  element  of  constant  valence.  Write  above  the  symbol  of 
each  element,  in  each  formula,  its  valence. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 
34 


Page  2 

Part  II 

{Omit  one  group.     Each  question  counts  10.) 

Group  A 

C.  (a)  Classify  as  oxidizing  or  reducing  agents  the  following  substances:    hot 
concentrated  H,S04,  H.S,  HOCl,  H^SO^,  concentrated  HNO3. 
ib)  Make  three  pairs  by  combinations  of  the  above  which  will  react  with  each 
other  to  form  new  substances. 

7.  (c)  Outline  briefly  a  laboratory  method  for  obtaining  a  pure  sample  of 

(1)  sulphur  crystals  from  powdered  sulphur,  (2)  ferric  hydroxide  from 
iron. 
{h)  Name  two  substances  which  in  reacting  upon  each  other  can  yield  (1)  an 
element  by  reduction  of  a  compound  of  that  element,  (2)  an  element 
by  oxidation  of  a  compound  of  that  element,  (3)  a  soluble  salt  by  direct 
combination,  (4)  an  insoluble  sulphide  by  precipitation. 

Group  B 

8.  Considering  each  of  the  following  statements  separately,  explain  why  you 

consider  it  to  be  an  experimental  fact  or  an  assumption:  (a)  The  composi- 
tion of  a  given  compound  does  not  vary.  (6)  Two  atoms  of  iron  have  the 
same  weight,  (c)  The  materials  composing  foods  cannot  be  put  out  of 
existence,  {d)  Some  compounds  ionize  when  dissolved  in  water,  (e)  Five 
grams  of  hydrogen  may  be  found  united  with  forty  grams  of  oxygen  or 
with  eighty  grams.     Name  the  theory  or  law  which  apphes  in  each  case. 

9.  A  dirigible  balloon  at  sea-level  contains  400,000  cubic  feet  of  gas  measured 

at  a  pressure  of  774  mm.  of  mercury  and  at  a  temperature  of  27°  C.  It 
rises  to  an  elevation  at  which  the  pressure  is  reduced  to  430  mm.  and  the 
temperature  to  —23°  C.  What  is  the  volume  of  the  gas  under  the  latter 
conditions,  assuming  that  none  is  allowed  to  escape  from  the  containers  ? 

Group  C 

10.  (c)  What  component  do  rice,  tapioca,  and  potatoes  have  in  common  ?    How 

could  this  component  be  identified  ? 
(6)  What  are  the  products  of  the  fermentation  of  glucose?    Why  do  the 

bubbles  of  gas  not  appear  at  once  in  this  fermentation  ? 
(c)  Describe  the  preparation  of  water  gas  and  write  an  equation  for  the 

reaction  involved. 

11.  How  could  it  be  determined  by  chemical  means  if  a  sample  of  (a)  water  were 

hard  or  soft?  {h)  hard  water  had  temporary-  or  permanent  hardness? 
(c)  washing  powder  contained  sodium  carbonate  ?  id)  metal  was  gold  or 
^rass?  (e)  beverage  contained  alcohol? 


COMPREHENSIVE  CHEMISTRY 


105350 


I9I6 

Comprehensive  Examination 


CHEMISTRY 

Friday,  June  23  9:00  a.m.-i  2:00  m. 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  a 
part  of  the  examination  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  questions  as  indicated  below. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Part  I 
{Answer  all  questions  in  Part  I.) 

1.  Discuss  concisely  the  important  classes  of  compounds — acids,  bases,  and 

salts — from  the  standpoint  of:  (a)  their  composition,  (6)  their  prepara- 
tion, (c)  their  properties.  Illustrate  your  answer  fully  with  formulas  and 
with  equations  for  reactions. 

2.  a)  Give  a  concise  statement  of  the  constitution  of  matter  according  to  the 

atomic  theory. 
b)  State  any  two  laws  fundamental  to  the  theory-,  and  show  how  this  theory 
explains  these  laws. 

3.  Write  equations  for  the  following  reactions,   using  formulas   throughout, 
r     The  equations  must  be  properly  balanced  to  receive  credit: 

a)  Sodium  acid  carbonate+hydrochloric  acid=  ? 

b)  Calcium  phosphate+sulphuric  acid  (in  excess)  =  ? 

c)  Copper + nitric  acid  (dilute)  =  ? 

d)  Ferric  nitrate+ammonium  hydroxide  =  ? 

e)  SiUca-|- sodium  carbonate  (fused)  =  ? 

4.  A  certain  quantity  of  magnesium  dissolved  in  acid  gave  exactly  100  c.c.  of 

dry  hydrogen  at  a  temperature  of  22°  C.  and  a  pressure  of  780  mm.     How 
many  grams  of  metal  were  used  ?     Compute  the  result  to  three  significant 
figures  (Mg=24.3). 
Note. — A  liter  of  hydrogen  at  o°C.  and  760  mm.  weighs  0.09  gm. 

5.  Chlorine  and  nitric  acid  often  act  as  oxidizing  agents,  sulphur  dioxide  and 

carbon  as  reducing  agents.  Explain  these  statements  and  give  examples, 
with  equations,  illustrating  these  actions.  State  any  necessary  conditions 
of  dilution  or  of  temperature. 

Part  II 
SUPPLEMENTARY  REQUIREMENTS 
Group  A 
{Answer  two  questions  from  this  group.) 

6.  Give  the  names  and  formulas  of  five  common  minerals  of  industrial  impor- 

tance.    State  what  commercial  use  may  be  made  of  each  of  them. 

(SEE  NEXT  PAGE) 
38 


7.  Classify  in  natural  groups  the  following  elements:   carbon,  calcium,  chlorine, 

barium,  bromine,  iodine,  and  silicon.  Indicate  the  relations  of  those  within 
each  group  by  comparing  the  formulas  and  the  properties  of  their  oxides 
or  hydrides  or  both. 

8.  Answer  any  two  of  the  following  questions: 

a)  Why  does  a  water  solution  of  ferric  chloride  give  an  acid  reaction,  while 

one  of  sodium  carbonate  gives  an  alkaline  reaction  ? 

b)  Account  for  the  fact  that  a  solution  of  common  salt  in  water  conducts 

the  electric  current,  while  one  of  sugar  does  not. 

c)  Which  exhibits  the  greater  osmotic  pressure,  a  gram-molecular  solution 

of  salt  or  one  of  cane  sugar  ?     Why  ?     Sketch  an  apparatus  for  demon- 
strating osmotic  pressure. 

9.  a)  How  would  you  proceed  in  order  to  get  large  crystals  from  a  solution  ? 

Small  ones  ? 
b)  Why  do  certain  crystalline  substances  on  exposure  to  the  air  crumble 
while  others  do  not  ? 

Group  B 
(Answer  one  question  from  this  group.) 

10.  At  standard  temperature  and  pressure,  one  liter  of  the  gaseous  element,  A, 

unites  with  three  liters  of  the  gaseous  element,  B,  to  make  two  liters  of  the 
gas,  C.  If  each  molecule  of  C  contains  one  atom  of  A ,  what  is  the  simplest 
formula  for  a  molecule  of  the  element  A  ?  Show  clearly  how  you  arrive  at 
your  conclusion. 

11.  One  gram  of  pure  iron  forms  i  .43  gm.  of  an  oxide.     Find  (a)  the  percentage 

composition  for  this  oxide  of  iron,  (6)  its  simplest  formula,  and  (c)  the 
equivalent  weight  of  iron  in  the  compound.     (Fe=  56,  O  =  16.) 

Group  C 
(Answer  two  questions  from  this  group.) 

12.  How  would  you  determine  by  chemical  tests  whether  (a)  "woolen"  goods 

contained  cotton,  (b)  baking  powder  contained  ammonium  compounds, 
(c)  water  contained  chlorides  ? 

13.  a)  State  the  composition  of  two  kinds  of  baking  powder. 

b)  Write  an  equation  for  the  reaction  which  occurs  when   one   of   these 

powders  is  moistened  with  water. 

c)  Explain  the  action  of  yeast  in  bread-making. 

14.  a)  Mention  two  compounds  of  nitrogen  that  are  used  as  fertilizers. 

b)  Wliat  natural  provision  is  there  for  converting  the  nitrogen  of  the  air 

into  plant  food  ? 

c)  Outline  one  artificial  process  for  the  fixation  of  atmospheric  nitrogen. 

15.  Give  the  method  of  keeping  and  the  necessary  precautions  in  the  storage 

of  each  of  the  following  substances:  (a)  sodium,  (b)  gasoline,  (c)  yellow 
(white)  phosphorus,  (d)  bromine,  (e)  hydrofluoric  acid. 

39 


I9i6 

Comprehensive  Examination 


CHEMISTRY 

Monday,  September  i8  2:00-5:00  p.m. 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  a 
part  of  the  examination  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  questions  as  indicated  below. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Part  I 
(Answer  all  questions  in  Part  I.) 

1.  a)  Define  the  terms  "molecule,"  "atom,"  and  "ion." 

b)  State  Avogadro's  h>T)othesis,  and  show  how  it  guides   the  chemist   in 
determining  molecular  weights. 

2.  a)  What  takes  place  when  steam  is  passed  over  heated  zinc  or  iron  ? 

b)  How  would  you  identify  the  products  ? 

c)  What  do  you  learn  about  the  composition  of  water  from  this  experiment  ? 

3.  Describe  the  action,  if  any,  and  represent  by  equations  the  chemical  changes 

taking  place  when  dilute  hydrochloric  acid  and  nitric  acid  are  added 
separately  to  each  of  the  following  substances:  (a)  ferric  hydroxide,  (b)  zinc 
oxide,  (c)  calcium  carbonate,  (d)  silver. 

4.  a)  Calculate   the   percentage   of    oxygen   in    crystalHzed    copper    nitrate, 

Cu(N03).-6H,0.     (Cu  =  64,  N=i4,  0  =  i6,  H=i.) 
b)  What  weight,  and  volume  at  0°  C.  and  760  mm.,  of  carbon  dioxide  can 
be  obtained  by  treating  an  excess  of  sodium  acid  carbonate  with  490  gm. 
of  sulphuric  acid  containing  20  per  cent  of  H^SO^  ?     (Na  =  23,  C  =  12, 
0=16,  H=i,  S  =  32.) 
Note. — A  liter  of  carbon  dioxide  at  o°C.  and  760  mm.  weighs  i  .97  gm. 

5.  Define  and  illustrate  with  an  example  each  of  the  following:    (a)  acid 

anhydride,  (b)  catalytic  agent,  (c)  saturated  solution,  (d)  subHmation, 
(e)  either  destructive  distillation  or  fractional  distillation. 

Part  II 
SUPPLEMENTARY  REQUIREMENTS 
'  Group  A 

(Answer  two  questions  from  this  group.) 

6.  Two  rods  of  copper  are  placed  in  a  solution  of  copper  sulphate.    What  takes 

place  when  a  current  of  electricity  is  passed  from  one  rod  to  the  other 
through  the  solution?  How  might  you  prove  what  happens  to  each  of 
the  copper  rods  ? 

(SEE  NEXT  PAGE) 
40 

/ 


7-  State  in  words  and  by  writing  equations  how  you  would  obtain:  (a)  Ferric 
chloride  from  ferrous  chloride;  (b)  ferrous  chloride  from  ferric  chloride; 
(c)  sodium  carbonate  from  sodium  hydroxide;  (d)  sodium  hydroxide  from 
sodium  carbonate;    (e)  oxygen  from  ozone;    (/)  ozone  from  ox^'gen. 

8.  How  would  you  prove,  by  chemical  means,  the  presence  in  air  of  each  of  the 

following  components:   (a)  water,  (b)  carbon  dioxide,  (c)  oxygen,  (d)  nitro- 
gen? 

9.  a)  Arrange  the  names  of  ten  common  elements  in  natural  groups. 

b)  Write  the  formula  for  one  oxide  of  each  and  state  what  acid  or  base  can 
be  formed  from  each  of  these  oxides. 

Group  B 

(Answer  two  questions  from  this  group.) 

10.  a)  A  compound  has  the  following  composition:    carbon,  54.67  per  cent; 

hydrogen,  9. 11  per  cent;  oxygen,  36.22  per  cent.     Find  the  simplest 
formula  for  the  substance.     (C  =  i2,  0=i6,  H=i.) 
b)  A  body  of  air  at  constant  pressure  occupies  a  volume  of  500  c.c.  at  20°  C. 
At  what  temperature  will  its  volume  become  1,000  c.c.  ? 

11.  How  many  liters  of  ammonia  gas,  measured  under  standard  conditions,  can 

be  obtained  when  20  gm.  of  sodium  hydroxide  react  with  an  excess  of 
ammonium  sulphate?     (Xa  =  23,  0=i6,  H  =  i,  N=i4,  8  =  32.) 
Note. — A  liter  of  ammonia  gas  at  o°C.  and  760  mm.  weighs  0.772  gm. 

12.  What  experimental  evidence  can  be  cited  to  show  (a)  that  chloride  ions  are 

not  molecules  of  chlorine  ?     {b)  that  chloride  ions  are  charged  with  nega- 
tive electricity  ? 

13.  Write  a  reversible  chemical  reaction  and  explain  how  it  may  be  made  to  go 

to  completion  in  either  direction. 

Group  C 
{Answer  one  question  from  this  group.) 

14.  a)  Make  a  diagram  of  an  acetylene  generator.     With  the  aid  of  an  equation, 

explain  its  operation. 

b)  Write  the  equation  for  the  complete  combustion  of  acetylene. 

c)  Why  does  acetylene  burn  with  a  flame  which  is  more  luminous   than 

that  of  methane  ? 

15.  Answer  any  two  of  the  following  questions: 

c)  Mention  a  necessary  property  that  must  be  possessed  by  an  oil  (i)  for 
soap-making,  (2)  for  mixing  with  paint,  (3)  for  a  lubricant.  Name  as 
an  example  some  particular  oil  for  each  use. 

b)  What  are  the  physical  and  chemical  differences  between  cast  iron  and 

steel ? 

c)  Why  does  iron,  in  the  course  of  time,  turn  completely  into  rust,  while 

aluminium  and  zinc  tarnish  only  slightly  ? 

41 


1917 
Comprehensive  Examination 


CHEMISTRY 

Friday,  June  22  2-5  p.m, 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  a  part 
of  the  examination  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  questions  as  indicated  below. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Part  I 
(Answer  all  questions  in  Pari  I.) 

1.  a)  Name  and  define  four  different  types  of  chemical  action,  and  illustrate 

each  by  an  experiment  which  you  have  performed  in  the  laboratory, 
stating  the  object  of  the  experiment,  together  with  the  names  of  the 
substances  used  and  of  the  products  formed. 
b)  What  is  meant  by  a  radical  ?     Give  an  example  to  show  how  a  radical  may 
be  decomposed  in  a  chemical  change. 

2.  c)  State  the  Law  of  Multiple  Proportions,  and  illustrate  it  by  the  considera- 

tion of  two  compounds  of  carbon  and  hydrogen  containing  respectively 
75  per  cent  and  92 . 3  per  cent  of  carbon. 
b)  How  does  this  law  support  the  hypothesis  that  the  elements  are  composed 
of  atoms  having  def-nite  weights  ? 

3.  a)  How  many  grams  of  hydrochloric  acid  gas  can  be  obtained  by  heating  ten 

grams  of  crystallized  ferric  chloride,  FeCl3'6H20,  with  concentrated 
sulphuric  acid?     (H  =  l,  0  =  16,  CI =35. 5,  Fe  =  56.) 

b)  What  is  the  percentage  of  sulphur  in  iron  alum,  K2S04-Fe2 (804)3  •.24H2O  ? 
(K=39,  S=32,  0  =  16,  Fe  =  56,  H  =  l.) 

4.  Give  a  detailed  account  of  a  good  laboratory  method  for  preparing  and 

collecting  chlorine  in  quantity;  write  the  chemical  equations  involved; 
make  a  diagram  of  the  apparatus. 

5.  Write  equations  for  the  following  reactions,  using  formulas   throughout. 

The  equations  must  be  properly  balanced  to  receive  credit. 

a)  Calcium  hydroxide  and  sulphurous  acid  =  ? 

b)  Steam  and  magnesium  (heated)  =  ? 

c)  Hydrogen  sulphide  burned  in  excess  of  oxygen  =  ? 

d)  Nitric  acid  and  ammonia  gas=  ? 

e)  Aluminium  sulphate  and  ammonium  hydroxide  =  ? 

(SEE  NEXT  PAGE) 
42 


Part  II 
(Answer  five  qtcestions  from  Part  II.     Extra  questions  will  receive  no  credit.) 

6.  Indicate  the  basic  oxides  in  the  following  list,  and  write  the  names  of  the 

compounds  formed  by  heating  them  with  the  acid  anhydrides  in  the  list: 
phosphorus  pentoxide,  calcium  oxide,  silicon  dioxide,  sulphur  trioxide,  and 
aluminium  oxide. 

7.  Compare  and  contrast  the  properties  and  uses  of  the  two  chlorides  of  mercury. 

Give  the  scientific  and  the  common  names;  also  the  formulas  of  these  com- 
pounds. 

8.  a)  What  volume  would  be  occupied  by  14  grams  of  carbon  monoxide  under 

standard  conditions  ?     (O  =  16,  C  =  12.) 

b)  If  ten  liters  of  carbon  monoxide  under  standard  conditions  are  heated  to 

27 . 3°  C,  without  change  in  pressure,  what  volume  will  tlie  gas  occupy  ? 

c)  What  volume  of  oxygen  is  necessary  to  combine  with  five  liters  of  carbon 

monoxide  under  the  same  conditions  of  temperature  and  pressure? 
Show  how  you  arrive  at  your  conclusion. 

9.  A  certain  chemical  compound  is  found  by  analysis  to  contain  92.3  per  cent 

of  carbon  and  7 . 7  per  cent  of  hydrogen.  WTiat  is  the  simplest  formula 
which  can  express  its  composition  ?  If  the  molecular  weight  is  78,  what 
is  the  formula  ?     (C  =  12,  H  =  1 .) 

10.  a)  If  steam  is  passed  over  heated  iron,  iron  oxide  and  hydrogen  are  formed; 

if  hydrogen  is  passed  over  heated  iron  oxide,  metallic  iron  and  steam 
are  formed.     W^hy  are  the  products  of  reaction  different  in  the  two 
cases? 
h)  Under  what  conditions  will  a  chemical  reaction  reach  equilibrium  ?     Under 
what  conditions  will  it  run  to  an  end  ? 

11.  Define  the  term  "molecular  weight,"  and  give  one  method  for  determining  a 

molecular  weight. 

12.  How  may  ozone  be  prepared  ?     What  are  its  properties  ?     How  is  its  formula 

written  ?  How  would  you  demonstrate  its  chemical  composition  (not  its 
formula)  ? 

13.  a)  Give  the  names  and  formulas  of  two  alcohols,  together  with  the  name 

and  formula  of  the  acid  derived  from  each. 
b)  Outline  a  process  for  tlie  commercial  production  of  grain  alcohol  and  state 
some  of  its  industrial  uses.     What  is  denatured  alcohol  ? 

14.  a)  Outline  a  method  for  the  manufacture  of  nitric  acid  from  atmospheric 

nitrogen  or  from  ammonia,  {b)  Enumerate  at  least  two  of  the 
important  commercial  uses  of  nitric  acid. 

15.  a)  Name  three  classes  of  food  substances  and  list  several  food  substances 

which  are  typical  in  each  class. 
b)  Describe  tests  by  which  the  nature  of  a  simple  food  substance  may  be 
determined. 


43 


1917 

Comprehensive  Examination 


CHExMISTRY 

Monday,  September  17  2-5  p.m. 

A  teacher's  certificate  covering  laboratory  instruction  must  be  presented  as  a  part  of 
the  examination  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  questions  as  indicated  below. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Part  I 

(Answer  all  questions  in  Part  I.) 

1.  Define,  and  give  at  least  one  example  of  (1)  diacid  base,  (2)  acid  salt,  (3)  redu- 

cing agent,  (4)  anion,  (5)  atom,  (6)  molecule. 

2.  a)  Define  and  give  three  examples,  of  neutralization,  describing  the  ionic 

changes  involved  in  the  reactions. 

h)  Define  and  give  an  example  of  hydrolysis.  How  can  the  litmus  reaction 
of  the  water  solution  of  a  normal  salt  be  predicted  from  its  composition  ? 
Illustrate  your  answer  by  an  example  of  a  salt  having  an  acid  reaction 
and  of  another  having  a  basic  reaction. 

3.  a)  State  Gay-Lussac's  law  of  combining  gas  volumes,  and  illustrate  with  an 

example.     State   the  hypothesis   which   serves    to   explain   the   facts 
generalized  by  this  law. 

b)  30  grams  of  chlorine  are  to  be  united  with  hydrogen.  What  volume  of 
hydrogen  is  required  at  0°  C.  and  760  mm.,  and  what  volume  of  hydro- 
gen chloride  results  under  the  same  conditions?     (CI  =  35.  5,  H=l.) 

Note. — A  liter  of  chlorine  at  0°  C.  and  760  mm.  weighs  3 .  22  grams,  and  a  liter  of  hydrogen 
0.09  gram. 

4.  a)  Name  and  describe  three  allotropic  forms  of  sulphur,  and  tell  how  each  is 

prepared. 

b)  Give  the  names  and  formulas  of  the  two  most  important  oxides  of  sulphur, 
and  show  by  means  of  chemical  equations  what  occurs  when  each  of 
these  oxides  is  treated  with  water. 

5.  Write  equations  for  the  following  reactions,  using  formulas  throughout.    The 

equations  must  be  properly  balanced  to  receive  credit: 

a)  Lead  nitrate  and  hydrogen  sulphide  =  ? 

b)  Copper  and  sulphuric  acid  (hot,  concentrated)  =  ? 

c)  Phosphoric  acid  and  barium  hydroxide  =  ? 

d)  Sodium  carbonate  and  acetic  acid=  ? 

e)  Ammonium  chloride  and  calcium  hydroxide  =  ? 

(SEE  NEXT  PAGE) 
44 


Part  II 
(Answer  five  questions  from  Part  II.     Extra  questions  will  receive  no  credit.) 

6.  a)  State  how  you  would  prove  whether  a  certain  salt  solution  is  unsaturated, 

saturated,  or  supersaturated. 
b)  How  do  chann;es  in  temperature  and  pressure  respectively  change  the 
solubility  in  licjuids  of  gases  and  of  solids  ? 

7.  a)  Mention   three  important   differences  between   the  water  solutions  of 

electrolytes  and  those  of  non-electrolytes.     How  are  these  differences 
explained  ? 
b)  Explain  fully  in  terms  of  the  ionization  theory  the  electrolysis  of  a  solution 
of  copper  sulphate. 

8.  A  balloon  requires  for  adequate  inflation  5,000  gram-molecular  volumes  (or 

an  equal  number  of  gram-molecules)  of  hydrogen,  measured  at  normal 
temperature  and  pressure.  What  is  the  cost  of  inflating  such  a  balloon 
if  scrap  iron  at  1  cent  per  kilogram  and  sulphuric  acid,  containing  20  per 
cent  of  H2SO4,  at  4  cents  per  kilogram,  are  used  for  generating  the  hydro- 
gen?   (Fe=56,  H  =  l,  S=32,  0=16.) 

9.  c)  Describe  the  production  of  ammonia  either  by  the  Haber  process,  or  from 

calcium  cyanamide.     (All  equations  are  required.) 
b)  Write  down  in  parallel  columns  fn-e  specific  physical  properties  of  am- 
monia, and  three  specific  chemical  properties. 

10.  a)  Describe  a  test  or  tests  to  distinguish  (1)  between  oxygen  and  nitrous 

oxide,  (2)  between  hydrogen  and  carbon  monoxide,  (3)  Ijetween  nitrogen 
and  carbon  dioxide. 
b)  State  briefly  the  effect  of  inhaling  each  of  these  gases  in  the  pure  state. 

11.  c)  How  would  you  determine  whether  a  given  sample  of  ammonia  gas  con- 

tained air  ? 
b)  Give  tests  for  free  chlorine,  bromine,  and  iodine  respectively;  give  also  a 
test  for  the  ions  of  the  same  elements. 

12.  Describe  two  important  chemical  industries  depending  directly  or  indirectly 

on  electrical  energy. 

13.  a)  Describe  the  "burning"  of  limestone.     Make  a  diagram  of  a  kiln,  and 

indicate  its  operation. 

b)  Distinguish  between  quicklime,  slaked  lime,  air-slaked  lime,  lime  water, 

and  milk  of  lime. 

c)  What  is  meant  by  "destructive  distillation"?     By  applying  this  process 

to  soft  coal,  what  products  are  obtained  ?  What  products  are  obtained 
by  applying  the  process  to  wood  ? 

14.  a)  What  is  "sterhng"  silver,  and  what  acid  should  be  used  to  dissolve  it? 

ib)  How  may  pure  silver  be  obtained  from  this  solution  ?  (c)  State  how 
articles  of  baser  metal  are  plated  with  silver,  and  how  mirrors  are  silvered. 
[d)  What  compound  of  silver  is  used  in  indelible  ink  ?  Explain  the 
chemical  changes  involved  in  its  use. 

15.  1.0085  grams  of  pure  tin  foil  were  oxidized  with  nitric  acid,  and  the  final 

weight  of  the  highly  ignited  oxide  was  1 .2790  grams.  From  the  data  sub- 
mitted, find  the  percentage  composition  and  the  simplest  formula  of  this 
oxide  of  tin.     (Sn  =  1 19,  0  =  1(3.) 


45 


1918 

Comprehensive  Examination 


CHEMISTRY 

Wednesday,  June  19  2-5  p.m. 

A  teacher's  certificate  covering  laboratory  instruction  must  be  presented  as  a  part  of 
the  examination  imless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory  exami- 
nation. 

Answer  ten  questions  as  indicated  below. 

Attach  to  the  answer,  in  each  case,  the  nimiber  and  letter  used  in  the  printed  paper. 

Part  I 
{Answer  all  questions  in  Part  I.) 

1.  Give  (a)  exact  statement,  (b)  experimental  proof,  and  (c)  a  practical  applica- 

tion of  one  of  the  fundamental  laws  of  chemistry. 

2.  a)  Outline  three  different  methods  for  obtaining  oxygen;  give  some  idea  of 

their  relative  cost. 

b)  Write  equations,  using  formulas,  to  show  how  each  of  three  metals  may  be 
obtained  from  ores  or  artilicial  compounds.  Each  method  involved 
should  be  different  from  the  others. 

3.  a)  Calculate  the  weight  of  manganese  dioxide  required  to  produce  chlorine 

enough  to  fill  a  flask  of  4  liters  capacity  when  the  barometer  stands  at 
760  mm.  and  the  temperature  is  0°  C.     (Mn.  =54.9, 0  =  16,  CI =35. 5.) 
Note — A  liter  of  chlorine  at  0°  C.  and  760  mm.  weighs  3.22  grams. 

b)  What  weight  of  manganese  dioxide  would  be  required  if  the  flask  were 
filled  at  760  mm.  and  273°  C.  ? 

4.  Give  the  formulas  of  two  oxides  of  sulphur,  one  oxide  of  nitrogen,  and  one 

oxide  of  carbon,  that  are  acid  anhydrides.  Show  by  equations  how  an 
acid  may  be  made  from  each  of  these,  and  give  the  name  of  the  acid  in  each 
case. 

5.  Write  equations  for  any  five  of  the  following  reactions,  using  formulas  through- 

out:    (The  equations  must  be  properly  balanced  to  receive  credit.) 

a)  Solid  sodium  nitrate  heated  with  solid  ammonium  chloride  =  ? 

b)  Hydrogen  sulphide  and  ammonia  =  ? 

c)  Phosphoric  acid  and  aluminium  hydroxide  =  ? 

d)  Sodium  iodide  and  chlorine  =  ? 

e)  Zinc  oxide  heated  with  hydrogen  sulphide  =  ? 

/)  Sodium  acid  carbonate  and  calcium  hydroxide  =  ? 

(SEE  NEXT  PAGE) 
46 


Part  II 
(Answer  five  questions  from  Part  II.     Extra  questions  will  receive  no  credit.) 

6.  a)  What  is  a  normal  solution  of  an  acid  ?  of  an  alkali  ? 

b)  10  c.c.  of  ordinary  household  ammonia  are  neutralized  by  the  addition  of 
40  c.c.  of  a  normal  solution  of  hydrochloric  acid.  What  weight  of 
ammonia  gas,  NH3,  is  contained  in  each  cubic  centimeter  of  the  original 
solution  ? 

7.  Discuss  {a)  the  extraction  of  sulphur  in  the  United  States  and  abroad;  {b)  its 

physical  and  chemical  properties;   (c)  its  uses. 

8.  a)  Give  an  example  of  a  chemical  change  brought  about  by  heat,  another  by 

light,  and  a  third  by  electricity.     Mention  three  chemical  reactions  the 
first  of  which  produces  heat,  the  second  light,  and  the  third  electricity. 
b)  Distinguish  between  exothermic  and  endothermic  reactions  and  illustrate 
each  by  means  of  an  example. 

9.  1 .8  grams  of  magnesium  displace  from  acid  1820  c.c.  of  hydrogen,  measured 

dry  at  740  mm.  pressure  and  20°  C.  Find  the  volume  of  this  gas  under 
standard  conditions  and  determine  the  valence  of  magnesium.  (Mg.  =  24 . 3, 
H  =  1 .  008.)     What  is  your  definition  of  valence  ? 

Note — The  weight  of  one  liter  of  hydrogen  under  standard  conditions  is  0.09  gram. 

10.  a)  What  is  an  electrolyte  ?    Distinguish  between  electrolysis  and  electrolytic 

dissociation. 

6)  If  a  strong  (active)  acid  is  added  to  the  salt  of  a  weak  acid  in  water  solution, 
what  becomes  of  the  four  different  ions  involved  ?  Illustrate  by  an 
example. 

11.  Describe  the  manufacture  of  any  one  of  the  following  substances,  giving  a 

diagram,  and  equations  whenever  possible:  (a)  Ethyl  alcohol;  {b)  water 
gas;   (c)  open-hearth  steel. 

12.  a)  What  danger  is  there  in  a  long-continued  scarcity  of  potassium  compounds  ? 

Why  has  there  recently  been  such  a  scarcity  in  this  country  ? 
b)  Make  a  list  of  the  sources  of  potassium  compounds.     Suggest  a  method  for 
extracting  a  potassium  compound  from  two  of  the  raw  materials  men- 
tioned. 

13.  a)  Outline  a  commercial  method  for  producing  metallic  aluminium,     {b)  How 

is  aluminium  used  to  produce  other  metals  from  their  oxides  ?  (c)  Ex- 
plain the  fact  that  aluminium  retains  its  bright  appearance  in  the  air. 
{d)  Mention  one  industrial  use  for  alum. 


(SEE  NEXT  PAGE) 

47 


14.  c)  Name  three  military  explosives  and  state  from  what  substances  each  is 

made. 

b)  To  what  element  does  each  of  these  owe  its  explosive  character  ? 

c)  State  briefly  how  two  of  the  following  substances  are  made:  (1)  Celluloid; 

(2)  mercerized  cotton;   (3)  collodion;   (4)  artificial  silk. 

15.  a)  Given  unlabeled  bottles  which  severally  contain  hydrochloric  acid,  nitric 

acid,  and  sulphurig  acid,  how  would  you  identify  each,  using  a  chemical 
test  in  each  case  ? 

b)  Give  one  test  by  which  you  would  determine  in  each  case  whether  the 
acid  is  dilute  or  concentrated. 


4» 


1918 

Comprehensive  Examination 


CHEMISTRY 

Monday,  September  16  2-5  p.m. 

A  teacher's  certificate  covering  laboratory  instruction  must  be  presented  as  a  part 
of  the  examination  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  questions  as  indicated  below. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Part  I 

(Answer  all  questions  in  Part  I.) 

1.  Define,  and  also  illustrate  by  means  of  at  least  one  example  in  each  case,  the 

following  terms:  (a)  element;  {b)  synthesis;  (c)  cation;  {d)  catalyzer; 
{e)  hydrolysis. 

2.  Write  equations  for  any  five  of  the  following  reactions,  using  formulas  through- 

out:    (The  equations  must  be  properly  balanced  to  receive  credit.) 

a)  Iron  and  dilute  sulphuric  acid=  ? 

b)  Lead  acetate  and  hydrochloric  acid  =  ? 

c)  Aluminium  hydroxide  and  sulphuric  acid=  ? 

d)  Ferrous  chloride  and  chlorine  water  =  ? 

e)  Copper  sulphate  and  barium  hydroxide  =  ? 

/)  Manganese  dioxide  and  concentrated  hydrochloric  acid  =  ? 

3.  10  grams  of  crystallized  ammonium  carbonate,  (NH4)2  C03'H20,  are  heated 

until  completely  decomposed  into  ammonia,  carbon  dioxide,  and  steam. 
What  will  be  the  total  volume  of  these  products  at  273°  C.  and  760  mm. 
pressure?     (0  =  1G,  N  =  14,  C  =  12,  H=l.) 

Note — Under  the  conditions  above,  liter  volumes  of  ammonia,  carbon  dioxide,  and  steam 
weigh  0 .  38  gram,  0 .  98  gram,  and  0 .  40  gram,  respectively. 

4.  State  Avogadro's  law  and  show  in  detail  how  this  law  guides  the  chemist  in 

determining  the  molecular  weights  of  gases  or  vapors. 

5.  a)  Name  and  describe  one  important  commercial  process  for  manufacturing 

sodium  carbonate,  giving  all  the  equations  involved. 
b)  How  may  sodium  acid  carbonate  be  distinguished  from  sodium  carbonate  ? 

Part  II 
{Answer  five  questions  from  Part  II.     Extra  questions  will  receive  no  credit.) 

6.  Two  grams  of  finely  divided  metallic  nickel  are  heated  with  a  quantity  of 

sulphur  slightly  in  excess  of  that  needed  for  complete  combination  until 
the  chemical  action  is  completed  and  the  excess  of  sulphur  is  vaporized. 
The  weight  of  the  product  formed  is  3.09  grams.  Give  Uie  name  of  the 
product,  find  its  percentage  composition  and  also  the  simplest  formula  by 
which  its  composition  may  be  expressed.     (Ni  =  58.7,  S=32.) 

(SEE   NEXT  PAGE) 
B  49 


7.  a)  Name  two  elements  which  are  liquid  at  ordinary  temperatures,     {h)  Name 

the  common  allotropic  forms  of  each  of  four  elements,  (c)  Name  two 
elements  having  exceptionally  high  melting-points,  and  state  how  this 
property  is  put  to  practical  use  in  case  of  each. 

8.  a)  Describe  briefly  an  experiment  to  determine  the  percentage  of  oxygen  in 

air.  {h)  State  as  fully  as  possible  the  composition  of  air.  (c)  Give 
three  proofs  that  air  is  a  mixture  and  not  a  compound. 

9.  a)  State  one  point  of  resemblance  and  one  point  of  difference  between  solu- 

tions and  compounds. 

b)  Define  precipitation  and  crystallization;  illustrate  each  by  means  of  an 

example. 

c)  How  are  the  freezing-point  and  the  boiling-point  of  a  solvent  affected  by 

dissolved  substances  ?     Give  a  practical  application  of  one  of  these  facts. 

10.  a)  Distinguish  between  chemically  pure  water  and  spring  water,     {h)  How 

may  water  be  purified  on  a  small  scale  for  household  use  ?  How  is  it 
purified  on  a  large  scale  for  a  city  supply?  (c)  Name  one  impurity 
which  renders  water  unfit  for  use  in  laundries  and  outline  a  practical 
method  for  removing  it. 

11.  a)  Define  the  terms  hydroxide,  anhydrous,  and  water  of  hydration  (crystal- 

hzation). 
h)  Show  that  hydration  is  a  reversible  reaction  by  discussing  the  commercial 
manufacture  and  use  of  plaster  of  Paris. 

12.  a)  Describe  the  manufacture  of  sulphuric  acid  by  the  contact  process. 

b)  Show  how  sulphuric  acid  is  used  to  produce  another  acid,  and  state  the 

principle  involved. 

c)  Write  the  ionic  equation  for  neutralizing  barium  hydroxide  with  sulphuric 

acid. 

13.  Make  a  list  of  five  gases  which  would  be  dangerous  to  life  if  contained  in  air 

to  the  extent  of  a  small  per  cent,  and  suggest  a  method  of  eliminatmg 
each  gas.  Only  a  single  impurity  is  assumed  present  in  any  one  of  the 
given  samples  of  air. 

14.  a)  How  may  crude  copper  be  refined  ?     {b)  State  the  physical  and  chemical 

properties  of  copper.  Write  an  equation  showing  the  action  of  hot, 
concentrated  sulphuric  acid  upon  the  metal,  (c)  Name  the  elements 
present  in  important  alloys  of  copper. 

15.  State  one  locality  in  which  each  of  the  following  substances,  respectively,  is 

found  in  relative  abundance:  iron  ore,  diamond,  petroleum,  sodium  nitrate, 
sulphur,  gold,  copper  ores,  phosphate  rock,  coal,  radium  compounds. 


50 


Page  1 

1919 

Comprehensive  Examination 
CHEMISTRY 

Wednesday,  June  18  2-5  p.m. 

Answer  ten  questions  as  indicated  below. 

Attach  to  the  answer,  in  each  case,  the  niunber  and  letter  used  in  the  printed  paper. 

Part  I 
(Answer  all  questions  in  Part  I.) 

1.  Define  and  give  an  example  of  (a)  catalysis,  (b)  equivalent  of  an  element, 

(c)  allotropy,  (d)  molecular  weight,  (e)  carbohydrate. 

2.  Write  equations  for  the  following  reactions,  using  formulas  throughout.    The 

equations  must  be  properly  balanced  to  receive  credit. 

a)  Sodium  chloride+ manganese  dioxide+concentrated  sulphuric  acid= 

b)  Ferric  chloride^- calcium  hydroxide  = 

c)  Lead  nitrate+ hydrogen  sulphide  (solutions)  = 

d)  Ammonium  sulphate+ sodium  hydroxide  = 

e)  Concentrated  nitric  acid  heated  = 

3.  a)  How  many  cubic  centimeters  of  oxygen,  measured  at  0°  C.  and  760  mm. 

can  be  obtained  by  the  complete  decomposition  of  one  kilogram  of 
3  per  cent  solution  of  hydrogen  peroxide,  H2Qj,  into  water  and  oxygen  ? 
(H  1,  O  16.) 

Note. — A  liter  of  oxygen  at  0°  and  760  mm.  weighs  1.43  grams. 

b)  What  is  the  percentage  of  silica,  Si02,  in  the  mineral  analcite, 

NaaSiOs-     Al2(Si03)3-2H20  ?     (Si  28,  Al  27,  Na  23,  O  16,  H  1.) 

4.  Explain  each  of  the  following  experimental  facts: 

c)  A  dilute  solution  of  potassium  chloride  has  a  lower  freezing-point  than  one 

of  sugar  of  the  same  concentration  measured  in  gram  molecules  per 
liter. 

b)  A  drop  of  concentrated  sulphuric  acid  on  a  wooden  table  makes  a  black 

spot. 

c)  Many  minute  gas  bubbles  appear  on  the  inside  of  a  glass  of  cold  water 

standing  in  a  warm  room. 

d)  Copper  does  not  Hberate  hydrogen  from  nitric  acid. 

e)  Concentrated  hydrochloric  acid,  if  added  to  a  saturated  solution  of  sodium 

chloride,  gives  a  white  precipitate. 

(THIS  EXAMINATION  IS  CONTINUED  OR  PAGE  2) 

5> 


Page  2 

6.  a)  Given  pure  samples  of  sodium  carbonate,  chloride,  nitrate,  sulphite,  and 
sulphate,  give  one  test  by  which  the  negative  (acid)  radical  in  each 
may  be  identified. 

b)  Write  equations  for  the  reaction  of  each  of  the  above  substances  with 
concentrated  sulphuric  acid  at  room  temperature. 


Part  II 
(Answer  five  questions  from  Pari  II.    Extra  questions  will  receive  no  credit.) 

6.  a)  Using  the  ionization  theory,  explain  the  equilibrium  in  a  dilute  solution 

of  sodium  chloride.  If  two  platinum  electrodes  are  introduced  and 
a  current  of  electricity  passed,  explain  in  detail  the  changes  at  the 
cathode. 

h)  Compare  the  degree  of  ionization  of  (1)  hydrochloric  acid  and  acetic 
acid,  (2)  ammonium  hydroxide  and  potassium  hydroxide,  in  water 
solutions  of  the  same  concentration. 

7.  a)  What  is  a  saturated  solution  of  a  solid  in  a  liquid? 

b)  How  does  increasing  the  temperature  affect  the  solubility  of  solids  in 
liquids  ? 

£)  In  what  two  ways  could  a  saturated  solution  of  sodium  chloride  in  water 
be  prepared?  How  could  you  satisfy  yourself  that  the  solution  is 
just  saturated  in  both  cases  ? 

8.  a)  State  the  Law  of  Multiple  Proportions. 

b)  Give  two  substances  to  illustrate  the  above  law  with  the  percentage 
composition  in  each  case. 

9.  One  hundred  Uters  of  dry  air  at  20°  C.  and  at  760  mm.  contain  0.078  gram  of 

carbon  dioxide.     What  is  the  proportion  by  volume  of  carbon  dioxide 
present  in  the  air  ? 
Note — One  liter  of  carbon  dioxide  at  0'  C  and  760  mm.  weighs  1 .98  grams. 

10.  a)  A  small  flask  contains  ferric  chloride  (yellow)  strongly  acidified  with  hydro- 
chloric acid.  A  quantity  of  iron  tacks  is  added,  and  the  flask  is  closed 
in  such  a  manner  as  to  permit  the  escape  of  gas  and  to  prevent  the 
entrance  of  air.  How  do  you  explain  the  loss  of  color?  Write  an 
equation  for  the  reaction. 

b)  On  exposure  to  air  the  yellow  color  of  the  solution  is  gradually  restored. 
Account  for  the  result.     Write  an  equation  for  the  reaction. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  3) 


Pages 

11.  a)  State  the  action  of  yeast  on  sugar. 

b)  Describe  the  function  of  baking  powder  in  cooking. 

c)  Give  one  process  for  softening  hard  water. 

d)  Why  does  the  flame  of  a  gas  stove  sometimes  "strike  back"  ?    How  can 

this  difficulty  be  remedied  ? 

12.  a)  In  the  smelting  of  iron  ore,  what  materials  enter  the  blast  furnace,  and 

what  is  the  function  of  each  ? 
b)  What  name  is  given  to  the  metal  produced  by  the  blast  furnace,  and  how 
does  it  differ  in  physical  properties  and  in  chemical  composition  from 
the  product  of  the  Bessemer  converter  ? 

13.  a)  Outhne  the  manufacture  of  sulphuric  acid  by  the  contact  process. 

b)  Indicate  the  importance  of  this  acid  in  the  manufacture  of  miUtary  explo- 
sives by  citing  two  processes  in  which  it  is  necessary. 

14.  Barium  carbonate  is  treated  with  a  quantity  of  boiUng  dilute  sulphuric  acid 

just  sufficient  for  complete  reaction.    Using  the  language  and  symbols  of  the 
ionization  theory  wherever  pertinent,  describe  what  takes  place. 

15.  What  experiment  would  you  make  to  distinguish  between: 

a)  Sodium  chloride  and  ammonium  chloride  ? 

b)  Potassium  iodide  and  potassium  bromide  ? 

c)  Glucose  and  cane  sugar  ? 

d)  Copper  oxide  and  manganese  dioxide  ? 

e)  Chlorine  water  and  bromine  water  ? 


53 


Page  1 

1919 

CHEMISTRY 

Monday,  September  15  2-5  p.m. 

Answer  ten  questions  as  indicated  below.  <||2^ 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 


Part  I 
(Answer  all  questions  in  Part  I.) 

1.  a)  Distinguish  between  a  chemical  law  and  a  chemical  theory. 

b)  Name  three  laws  dealing  with  weights;  three  dealing  with  gases. 

c)  Name  two  important  theories  in  chemistry. 

2.  Discuss  sulphuric  acid  with  reference  to: 

a)  Its  physical  and  chemical  properties. 

b)  Four  of  its  important  uses. 

c)  One  process  of  manufacture. 

3.  Write  equations  for  the  following  reactions,  using  formulas  throughout.     The 

equations  must  be  properly  balanced  to  receive  credit: 

a)  Ethyl  alcohol  burned  completely  in  oxygen = 

b)  Hydrogen  sulphide+ chlorine  (in  solution)  = 

c)  Silver  nitrate+ calcium  chloride  = 

d)  Nitric  oxide-f  oxygen  gas= 

e)  Ferric  chloride + sulphuric  acid  (concentrated)  = 

4.  a)  How  many  cubic  centimeters  of  carbon  dioxide,  CO2,  measured  at  0°  and 

760  mm.,  will  be  absorbed  by  a  solution  containing  2  grams  of  sodium 
hydroxide,  to  form  sodium  carbonate  and  water?  (Na  23,  O  16, 
C  12,  H  1.) 

Note. — One  liter  of  carbon  dioxide  at  0°C.  and  760  mm.  weighs  1 .98  grams. 

b)  The  formula  of  a  gaseous  compound  is  C2H2.     Calculate  its  percentage 
composition  and  its  vapor  density. 

5.  a)  Why  does  wood  burn  with  a  flame  while  charcoal  merely  glows  ? 

b)  Can  you  light  a  jet  of  o.xygen  in  an  atmosphere  of  (1)  air,  (2)  hydrogen  ? 

Explain. 

c)  Describe  and  explain  the  successive  effects  observed  when  a  thin  strip  of 

copper  is  passed  very  slowly  through  a  Bunsen  flame. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 

54 


Page  2 

Part  II 
(Answer  five  questions  from  Part  II.     Extra  questions  will  receive  no  credit.) 

6.  a)  Give  directions  for  making  a  normal  solution  of  sulphuric  acid  and  one  of 

sodium  hydroxide. 

b)  Ten  cubic  centimeters  of  a  normal  solution  of  sulphuric  acid  requires 
2.5  cc.  of  a  solution  of  sodium  hydroxide  for  complete  neutralization. 
Find  the  concentration  of  the  solution  of  sodium  hydroxide  in  grams 
per  hter.     (S  32,  Na  23,  O  16,  H  1.) 

7.  The  water  solutions  of  certain  substances  give  the  following  tests:  What  may 

be  the  dissolved  substance  in  each  case  ? 

a)  The  solution  turns  blue  litmus  red  and  forms  with  silver  nitrate  solution 

a  white  precipitate  insoluble  in  nitric  acid. 

b)  The  solution  gives  a  deep-red  color  with  ammonium  or  potassium  thio- 

cyanate  (NH4CNS  or  KCNS),  and  with  barium  chloride  solution  a  white 
precipitate  insoluble  in  hydrochloric  acid. 

c)  The  solution  gives  a  blue  coloration  with  iodine. 

d)  The  solution  colors  the  Bunsen  flame  violet  and  forms  a  brown  ring  when 

it  is  mixed  with  concentrated  sulphuric  acid  and  ferrous  sulphate  solu- 
tion is  added. 

e)  The  solution  colors  the  Bunsen  flame  yellow  and  turns  red  Utmus  blue, 

8.  Calculate  the  molecular  weight  of  carbon-dioxide  gas  from  the  following  data, 

showing  clearly  every  step  of  the  calculation: 

Weight  of  flask  filled  with  CO2,  dry  =  102 .  38  grams 

Weight  of  flask  filled  with  air,  dry  =  101 .56  grams 

Temperature  of  measured  gases  =     0°  C. 

Pressure  of  measured  gases  =770  mm. 

Volume  of  flask  =1200cc. 

Note. — One  liter  of  air  at  0°  C.  and  760  mm.  weighs  1 .29  grams. 

9.  Outline  one  practical  method  for  the  preparation  of  each  of  the  following 

substances:  (a)  nitrogen  from  the  air,  (6)  carbon  mono.xide,  (c)  calciiun 
oxide,  {d)  glucose.  Mention  one  industrial  use  for  each  of  the  above- 
mentioned  substances. 

10.  a)  What  do  the  following  terminations  indicate,  -ite,  -ic,  -ide,  -ate,  -oiis? 

b)  What  relation  does  the  combining  weight  of  an  element  bear  to  its  atomic 
weight  ? 

11.  a)  Describe  the  laboratory  preparation  of  ammonia  and  mention  its  most 

important  properties. 

b)  How  can  ammonia  be  made  conmiercially  from  the  elements  ? 

c)  In  what  way  can  ammonia  be  used  in  the  manufacture  of  explosives  ? 

(TfflS  EXAMINATION  IS  CONTINUED  ON  PAGE  3) 


Page  3 

12.  a)  Outline   a   simple   process   for   making  soap  and  explain  the  chemical 

reaction  which  takes  place  in  its  formation  (without  equation). 

b)  Account  for  the  action  upon  litmus  paper  of  a  solution  of  a  soap  which 

contains  no  free  alkali. 

13.  Five  liters  of  carbon  monoxide  are  mixed  with  just  enough  oxygen  for  com- 

plete combustion  and  the  mixture  is  ignited.  If  the  original  gases  are 
measured  at  20°  C,  at  what  temperature  will  the  product  occupy  the  same 
volume,  the  pressure  remaining  the  same  ? 

14.  State  the  reason  for  each  of  the  following  precautions: 

c)  Potassium  chlorate  and  manganese  dioxide,  for  making  oxygen,  must  not 

be  ground  too  finely  together. 

b)  A  hot  object  should  be  cooled  before  weighing. 

c)  Concentrated  solutions  of  acid  and  alkali  should  not  be  mixed  without 

previous  dilution. 

d)  Phosphorus  should  not  be  handled  with  the  fingers. 

15.  a)  Write  equations  illustrating  three  different  methods  for  making  sodium 

sulphate. 

b)  Select  any  two  of  these  equations  and  tell  why  the  reaction  goes  to  com- 
pletion in  each  case. 


Is 


5(3 


Page  1 

1920 
Comprehensive  Examination 

CHEMISTRY 

Wednesday,  June  23  2-5  p.m. 

Answer  ten  questions  as  indicated  below, 

Niunber  and  letter  your  answers  to  correspond  to  the  questions  selected. 

Part  I 
(Answer  all  questions  in  JPart  I.) 

1.  Classify  the  following  compounds  into  (o)  acids,  {h)  bases,  (c)  salts,  {d)  acid 

anhyrides,  {e)  substances  belonging  to  none  of  the  foregoing  four  classifica- 
tions: sulphur  dioxide,  calcium  oxide,  ammonium  carbonate,  iron  sulphide, 
sodium  hydroxide,  phosphorus  pentoxide,  barium  chloride,  hydrogen 
sulphide. 

2.  Write  equations  for  the  following  reactions,   using  formulas  throughout. 

The  equations  must  be  properly  balanced  to  receive  credit.  Indicate  by 
reversed  arrows  those  reactions  which  do  not  go  almost  to  completion. 

a)  Silver+hot  concentrated  sulphuric  acid=  (sulphur  dioxide  is  formed). 

h)  Ammonium  sulphate  heated  with  sodium  chloride  = 

c)  Carbon  disulphide  burned  in  an  excess  of  ox}'gcn  = 

d)  Sodium  chloride,  carbon  dioxide,  ammonia,  and  water = 

e)  Hydrogen+ nitrogen,  heated  with  a  catalyzer  = 

3.  Baking  powder  can  be  made  by  mixing  baking  soda,  NaHCOs,  and  cream  of 

tartar,  HKC4H4O6.  These  substances  react  according  to  the  following 
equation: 

NaHC03+HKC4H406  =  H20+C02+NaKC4H406 

a)  How  much  cream  of  tartar  should  be  mixed  with  one  kilogram  of  baking 

soda  so  that  neither  ingredient  will  be  in  excess  ? 
h)  WTiat  volume  of  carbon  dioxide  at  0°  C.  and  760  mm.  may  be  obtained 

from  the  baking  powder  thus  made  ?     (K  39,  Na  23,  O  16,  C  12,  H  1.) 
Note. — One  liter  of  CO2  at  0°  C  and  760  mm.  weighs  1.98  grams. 

4.  a)  What  is  the  relation  between  volume  and  pressure  of  a  gas  when  the 

temperature  is  constant?  between  volume  and  temperature  when  the 
pressure  is  constant  ?  between  temperature  and  pressure  when  volume 
is  constant  ? 

h)  From  the  standpoint  of  the  molecular  hypothesis  explain  the  fact  that 
(1)  40  gallons  of  o.xygen  may  be  forced  into  a  small  steel  cylinder,  (2)  gas 
escapes  from  a  glass  of  soda  water,  (3)  chlorine  gas,  although  heavier 
than  air,  escapes  from  an  upright  vessel. 

5.  Tell  how  you  would  determine  experimentally  (a)  either  the  equivalent  of 

some  element  or  the  molecular  weight  of  some  gas;  {b)  either  the  percentage 
of  carbon  dioxide  in  exhaled  air  or  of  oxygen  in  ordinary  air.  Indicate 
the  method  of  computing  the  result  in  each  case. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

Part  II 
(Answer  five  questions  from  Part  11.     Extra  questions  will  receive  no  credit.) 

6.  Explain  each  of  the  following  facts: 

a)  Painters'  rags  sometimes  take  fire  spontaneously. 

b)  Concentrated  rather  than  dilute  sulphuric  acid  is  used  in  making  hydro- 

chloric acid. 

c)  Acetic  and  nitric  acid  solutions  of  the  same  concentration  in  gram  mole- 

cules per  liter  do  not  conduct  electricity  equally  well. 

d)  When  the  stopper  is  removed  from  a  bottle  containing  concentrated  hydro- 

chloric acid,  white  fumes  are  sometimes  observed. 

e)  A  solution  of  sodiiun  carbonate  has  an  alkaUne  reaction. 

7.  Indicate  the  difference  in  meaning  between  (a)  ion  and  radical,  (J)  electrolysis 

and  ionization,  (c)  equivalent  and  atomic  weight  of  an  element,  {d)  hydrate 
and  hydroxide,  (e)  monobasic  and  dibasic  acid.     Give  an  example  of  each, 

8.  A  portable  gas  stove  used  in  heating  a  room  burns  natural  gas  (assumed  to  be 

pure  methane,  CH4)  and  consumes  in  one  hour  10  cubic  feet  of  gas  measured 
at  a  pressure  of  30  inches  of  mercury  and  at  a  temperature  of  60°  F.  What 
volume  of  oxygen  is  consumed  and  what  space  is  occupied  by  the  carbon 
dioxide  which  is  produced,  when  measured  under  conditions  of  pressure 
and  temperature  previously  specified  ?  If  1  cubic  foot  of  methane  under 
these  conditions  weighs  0.04225  lbs.,  what  weight  of  water  vapor  is  formed 
during  the  combustion  ?     (O  16,  C  12,  HI.) 

9.  State  one  practical  use  for  each  of  the  following  substances,  suggested  by  the 

property  mentioned.  Give  in  each  case  an  example  of  such  a  substance, 
(a)  A  metal  having  a  very  high  melting-point,  {b)  a  substance  from  which 
a  water  solution  having  a  very  low  freezing-point  may  be  made,  (c)  an  acid 
having  a  high  boiling-point,  {d)  a  solid  or  liquid  capable  of  sudden  conversion 
into  gases  at  high  temperature,  ie)  a  volatile,  non-inflammable  liquid. 

10.  How  could  you  obtain   (a)  sulphur  from  hydrogen  sulphide,   {b)  metallic 

copper  from  copper  oxide,  (c)  potassium  nitrate  crystals  from  potassium 
chloride,  id)  ferric  oxide  from  ferric  chloride  ? 

11.  Two  gram  molecules  of  the  oxide  RO  combine  with  44.8  liters  of  oxygen  at 

0°  and  380  mm.  pressure.  The  volume  of  the  product,  under  the  same 
conditions,  is  nearly  equal  to  that  of  the  oxygen  taken.  Calculate  the 
formula  of  the  product. 

12.  a)  Name  the  products  when:   silica  is  fused  with  sodium  carbonate;   when 

dilute  sulphuric  acid  acts  on  magnesium. 

b)  Give  two  uses  for  each  of  the  following  substances:  ammonium  hydroxide, 

borax. 

c)  Why  is  nitric  acid  a  better  solvent  for  silver,  lead,  and  mercury  than  hydro- 

chloric acid  ? 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  3) 


Page:? 

13.  Why  should  sulphur  compounds  be  removed  from  illuminating  gas?  phos- 

phorus from  steel  ?  dust  from  sulphur  dioxide  in  the  contact  process  for 
making  sulphuric  acid  ?  moisture  from  materials  for  making  baking 
powders  ?  calcium  and  magnesium  chlorides  from  table  salt  ? 

14.  a)  Why  does  the  admission  of  air  at  the  base  of  the  Bunsen  burner  make  the 

flame  non-luminous  ? 

b)  Why  is  the  temperature  of  a  flame  of  hydrogen  burning  in  oxygen  higher 

than  that  of  hydrogen  burning  in  air  ? 

c)  Why  is  a  mixture  of  fine  coal  dust  and  air  explosive  ? 

15.  a)  What  property  has  helium  which  makes  it  better  than  hydrogen  for  filling 

balloons  ? 

b)  How  does  commercial   copper  compare  in    purity    with    other    metals 

as  commercially  supplied  ?     Describe  briefly  the  refining  of  copper. 

c)  Mention  three  substances  commonly  used  for  extinguishing  fire.     Indi- 

cate the  one  that  you  consider  best  adapted  to  extinguishing  burning 
gasoline. 


59 


Pagel 

1920 

CHEMISTRY 

Monday,  September  20  2-5  p.m. 

Answer  ten  questions  as  indicated  below. 

Number  and  letter  your  answers  to  correspond  to  the  questions  selected. 

Part  I 
(Answer  all  questions  in  Part  I.) 

1.  Write  equations  for  the  following  reactions,  using  formulas  throughout.     The 

equations  must  be  properly  balanced  to  receive  credit. 

a)  Nitric  acid  on  ammonium  carbonate  = 

h)  Silver  nitrate  solution  and  magnesium  chloride  solution  = 

c)  Hydrochloric  acid  and  oxygen  (with  a  catalytic  agent)  = 

d)  Calcium  phosphate  and  sulphuric  acid  = 

e)  Hydrogen  sulphide  on  lead  nitrate  solution  = 

2.  a)  What  particular  properties  are  used  in  recovering  the  sulphur  from  a  solu- 

tion in  carbon  disulphide  ? 
h)  What  chemical  tests  are  used  in  recognizing  sulphuric  acid  ?    a  chloride  ? 
nitrous  oxide  ? 

3.  a)  Fifty  cubic  centimeters  of  a  solution  containing  40  grams  of  sodium 

hydroxide  per  liter  neutralize  40  cc.  of  a  solution  of  hydrochloric  acid. 
WTiat  is  the  concentration  of  the  acid  solution  in  grams  per  hter? 
(CI  35.5,  Na  23,  O  16,  H  1.) 
h)  How  many  grams  of  potash  alum  (K2S04'Al2(S04)3*24  H2O)  can  be  made 
from  69  grams  of  bauxite  (AI2O3  •  2  H2O)  ?     (K  39,  S  32,  Al  27, 0 16,  H 1.) 

4.  Carbon  dioxide  gas  in  excess  is  passed  into  a  water  solution  of  sodium  carbonate. 

Write  an  equation  to  express  the  chemical  change  which  takes  place.  The 
resulting  solution  is  boiled  vigorously  for  some  time.  Write  an  equation 
to  represent  the  reaction  and  name  the  substance  which  is  left  in  the  solu- 
tion.    Explain  why  these  reactions  proceed  in  opposite  directions. 

5.  a)  WTiy  is  sulphuric  rather  than  hydrochloric  acid  used  in  making  nitric  acid  ? 

b)  Why  is  hydrochloric  rather  than  nitric  acid  used  in  making  hydrogen 

sulphide  ? 

c)  Why  is  hydrochloric  rather  than  sulphuric  acid  used  in  making  carbon 

dioxide  from  marble  ? 

d)  Why  is  sulphuric  rather  than  hydrochloric  acid  used  in  preparing  oxygen 

from  water  by  electrolysis  ? 

e)  Why  is  nitric  rather  than  hydrochloric  acid  used  to  dissolve  a  silver  coin  ? 
/)  Why  is  dilute  rather  than  concentrated  sulphuric  acid  used  in  making 

hydrogen  ? 

(THIS  EXAMINATION  IS  CONTINUED   ON  PAGE  2) 

60 


« 


Page  2 

Part  II 
(Answer  five  questions  frotn  Fart  II.     Extra  questions  will  receive  no  credit.) 

6.  A  liter  of  a  certain  elementary  gas  weighs  7.50  grams,  while  a  liter  of  hydrogen 

gas  under  the  same  conditions  weighs  0.050  gram.  The  atomic  weight 
of  the  element  composing  the  gas  is  75.  How  many  atoms  are  there  in 
one  molecule  of  the  gas  ? 

7.  a)  Mention  three  methods  of  increasing  the  speed  of  a  reaction  and  give  a 

practical  illustration  of  the  application  of  each  method. 
h)  If  sodium  is  exposed  to  air,  what  product  is  finally  obtained  ?    How  is 
sodium  usually  preserved  in  the  laboratory  or  stockroom  ? 

8.  What  experiment  would  demonstrate  that  (a)  silver  nitrate  contains  a  metal  ? 

{b)  sodium  carbonate  is  a  salt?  (c)  bromine  is  more  active  chemically 
than  iodine  but  less  so  than  chlorine?  {d)  iron  is  a  reducing  agent? 
(f)  chlorine  bleaches  only  indirectly  ? 

9.  a)  In  what  two  ways  can  ammonium  chloride,  without  reacting  chemically 

with  any  other  substance,  be  split  up  into  two  parts  ?     Specify  in  each 
case  the  conditions  under  which  complete  recombination  will  take  place. 
h)  Why  is  hydrogen  more  rapidly  evolved  by  zinc  reacting  with  hydrochloric 
acid  than  with  acetic  acid  of  the  same  concentration  ? 

10.  a)  A  certain  weight  of  potassium  carbonate,  heated  with  10  grams  of  sand, 

gives  25.6  grams  of   potassium    silicate    according    to   the   equation 
KoC03+SiOo  =  KoSi03+C02.     Calculate  the  weight  of  the  potassium 
carbonate.     (K  39,  Si  28,  O  IG,  C  12.) 
b)  What  is  the  percentage  of  sulphur  trioxide  in  white  vitriol  (ZnS04  •  7H2O)  ? 
(Zn  65,  S  32,  O  16,  H  1.) 

11.  a)  Assume  X  to  be  a  gaseous  element  having  a  valence  of  three  and  containing 

two  atoms  per  molecule.    To  make  two  volumes  of  its  gaseous  compound 
with  hydrogen,  how  many  volumes  of  each  constituent  are  required  ? 
State  the  law  upon  which  }-our  conclusion  is  based. 
b)  From  the  standpoint  of  the  electrolytic  dissociation  theory,  what  takes 
place  when  dilute  solutions  of  an  acid  and  a  base  are  mixed  ? 

12.  Which  is  the  more  specific  term  in  each  of  the  following  pairs:  (a)  dissociation 

or  ionization,  {b)  carbohydrates  or  sugars,  (c)  fermentation  or  decomposi- 
tion, {d)  halogen  acids  or  binary  acids  ?  Considering  each  of  the  foregoing 
pairs  separately,  cite  a  particular  case  illustrating  the  more  general  term 
which  is  not  included  by  the  more  specific. 

13.  a)  Give  two  diflferent  general  methods  for  the  formation  of  an  acid.     Illus- 

trate each  by  an  example  giving  equations  for  the  reactions  involved. 
Are  there  analogous  methods  for  the  formation  of  bases?     Illustrate 
by  equations. 
b)  Sodium  sulphate  and  copper  sulphate  are  dissolved  in  separate  portions 
of  pure  water.     Do  the  two  solutions  aflfect  litmus  alike  ?     Explain. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  3)  ^^ 


Page  3 

14.  Name  or  describe  one  useful  property  of  each  of  the  following  substances, 

and  give  one  use  made  of  it  because  of  this  property :  blaked  lime,  distilled 
water,  charcoal,  sulphur  dioxide,  aluminium,  sodium  nitrate,  cast  iron, 
copper  sulphate,  coke,  lead. 

15.  a)  How  can  decomposed  organic  matter  be  removed  from  water  without      J^ 

distillation  ? 

b)  How  can  bacteria  in  drinking-water  be  destroyed  without  raising   its 

temperature  ? 

c)  How  can  temporary  hardness  in  water  be  removed  without  raising  its 

temperature  ? 

d)  How  can  water  be  freed  from  dissolved  ammonia  ? 


62 


DRAWING  —  FREEHAND 


63 


1916 


DRAWING— FREE-HAND 


Saturday 


9: 00  a.m.     Two  hours 


Candidates  must  do  both  exercises,  including  both  a  and  b  in  exercise  1. 

No  more  than  forty-five  minutes  should  be  devoted  to  the  first  exercise.  If  this 
is  not  completed  by  9:45  a.m.,  it  should  be  left  imfinished  and  work  should  be  begun  on 
the  second  exercise.  If  this  should  be  finished  before  11  a.m.,  the  candidate  is  at  liberty 
to  devote  the  remaining  time  to  the  completion  of  the  first  exercise. 

An  incomplete  drawing,  correctly  laid  out  and  executed  by  correct  method,  is  better 
evidence  of  proficiency  than  a  completed  drawing  incorrect  in  construction  and  slovenly 
in  execution. 

Use  a  soft  pencil,  with  a  light  touch. 

All  work  must  be  strictly  free-hand  work  without  assistance  from  measuring  slips, 
instruments,  or  artificial  aids  of  any  kind. 

Accuracy  of  form  is  of  more  account  than  finished  execution. 

Students  must  not  erase  the  construction  lines. 


1.  a)  Make  a  line  drawing  in  perspective  of  a  hollow  cylinder  lying  on  a  horizontal 
plane  with  its  axis  turned  at  an  angle  of  about  60°  to  the  picture  plane. 
Make  the  length  of  the  cylinder  equal  to  its  diameter. 
Make  the  greatest  dimension  of  the  drawing  about  4  inches.  Show  all 
construction  lines  which  indicate  the  position  of  vanishing  points, 
drawing  them  with  a  light  touch. 

h)  Make  a  line  drawing  in  perspective  of  the  bench  shown  in  Fig.  1  turned  at 
an  angle  of  about  45°  to  the  picture  plane. 


Ti- 
ll 


-Ti- 
ll 


irni 


Fig.  1 

Make  the  greatest  dimension  of  the  drawing  about 
5  inches.  Show  all  construction  lines  which  indicate 
the  position  of  vanishing  points,  drawing  them  with 
a  light  touch. 


64 


(SEE  NEXT  PAGE) 


2.  Make  a  drawing  in  light  and  shade,  without  regard  to  color  value,  of  Fig.  2  or 
Fig.  3. 


<-       "'^. 


fi(^:-r 


Fig.  2 

In  Fig.  2  the  decoration  on  the  plate  and  bowl  shown  by  distinctions  of  color 
value  should  be  omitted  or  indicated  only  in  line.  In  Fig.  3  the  background 
should  be  omitted. 

Make  the  drawing  the  same  size  as  the  figure. 

(SEE  NEXT  PAGE) 

^5 


Fig.  3 


66 


1917 

DRAWING— FREE-HAND 

Saturday  9  a.m.     Two  hours 

Candidates  must  do  both  exercises,  including  both  (a)  and  (b)  in  exercise  1. 

An  incomplete  drawing,  correctly  laid  out  and  executed  by  correct  method,  is  better 
evidence  of  proficiency  than  a  completed  drawing  incorrect  in  construction  or  slovenly 
in  execution. 

Use  a  soft  pencil,  with  a  light  touch. 

All  work  must  be  strictly  free-hand  work  without  assistance  from  measuring  slips, 
instruments,  or  artificial  aids  of  any  kind. 

Accuracy  of  form  is  of  more  account  than  finished  execution. 

Students  must  not  erase  the  construction  lines. 

1.  a)  Represent  a  jelly  layer  cake,  circular  in  plan,  with  a  wedge-shaped  slice  cut 

from  it,  the  cut  going  to  the  center.     The  cake  is  placed  on  a  horizontal 
plane  below  the  level  of  the  eye.     Show  the  slice  lying  near  the  cake. 

Make  the  drawing  not  less  than  4  inches  in  width. 
b)  What  is   the  difference   between  perspective   projection   and   geometric 
projection  ? 

Answer  this  question  in  writing,  illustrating  by  diagrams. 

2.  Make  a  drawing  in  light  and  shade,  without  regard  to  color  value,  of  Fig.  1  or 

Fig.  2. 
In  Fig.  1  the  painted  decoration  on  the  cup,  shown  by  distinctions  of  color 

value,  should  be  omitted,  or  indicated  only  in  line. 
Make  the  drawing  the  same  size  as  the  figure. 


(SEE  NEXT  PAGE) 

67 


"~~1 


.  *-^f>««s-V^5ai*-W5fT'?'^*' 


i:^ 


(SEE  NEXT  PAGE) 


68 


Fig.  2 


U) 


1918 

DRAWING— FREE-HAND 

Saturday,  June  22  9  a.m.    Two  hours 

Candidates  must  do  all  exercises. 

An  incomplete  drawing,  correctly  laid  out  and  executed  by  correct  method,  is  better 
evidence  of  proficiency  than  a  completed  drawing  incorrect  in  construction  or  slovenly  ^^^ 

in  execution.  ^^ 

All  work  must  be  strictly  free-hand  work  without  assistance  from  measuring  slips, 
instruments,  or  artificial  aids  of  any  kind. 

1 .  a)  A  cylinder  stands  on  one  end. 

Make  three  perspective  drawings  of  equal  dimensions  to  represent  the 
cylinder  under  the  following  conditions: 

(1)  Eye  level  even  with  top  surface; 

(2)  Eye  level  half-way  between  upper  and  lower  surfaces; 

(3)  Eye  level  a  little  above  top  of  cylinder. 

The  axis  of  the  cylinder  should  be  about  double  its  diameter. 
Make  each  drawing  about  4  inches  in  its  largest  dimension. 

b)  Make  a  line  drawing  in  perspective  of  a  bureau,  turned  at  an  angle  to  the 

observer.     Let  there  be  at  least  three  drawers  in  the  bureau,  the  lowest 
one  being  open  half-way.     Do  not  show  thicknesses. 
Show  all  construction  lines  which  indicate  the  position  of  vanishing  points, 
drawing  them  with  a  light  touch. 

c)  Define:  (1)  Vanishing  Point; 

(2)  Vanishing  Line.  4  I 

2.  Make  a  drawing  in  light  and  shade,  without  regard  to  color  value,^  of  the 

subject  shown  in  the  figure. 
Make  the  drawing  the  same  size  as  the  figure. 

1  By  color  value  is  meant  the  degree  of  lightness  or  darkness  due  to  the  actual  color  (the 
local  tone)  of  the  object. 


(SEE  NEXT  PAGE) 


Page  1 

1919 
DRAWING— FREE-HAND 

Saturday,  June  21  9  a.m.     Two  hours 

Candidates  must  do  all  exercises. 

An  incomplete  drawing,  correctly  laid  out  and  executed  by  correct  method,  is  better 
evidence  of  proficiency  than  a  completed  drawing,  incorrect  in  construction  or  slovenly 
in  execution. 

All  work  must  be  strictly  free-hand  work  without  assistance  from  measuring  slips, 
instruments,  or  artificial  aids  of  any  kind. 

1.  Make  a  line  drawing  in  perspective  of  the  following  subject: 

A  rectangular  box  standing  in  the  corner  of  a  room,  with  a  side  of  the  box 

touching  each  wall;  a  cylindrical  box  standing  on  the  top  of  the  rectangular 

box. 
The  top  of  the  cylindrical  box  is  shghtly  below  the  eye  level. 
Draw  lines  to  indicate  the  walls,  the  floor,  and  the  ceiling  of  the  corner  of  the 

room. 
Do  not  show  thicknesses. 
Using  light  lines,  draw  the  horizon  line  and  all  construction  lines  which  indicate 

the  position  of  vanishing  points. 

2.  What  is  perspective  projection  as  distinguished  from  geometric  projection  ? 

3.  Make  either  a  drawing  in  line  only  from  Fig.  1,  or  o,  drawing  in  hght  and 

shade,  without  regard  to  color  value, ^  from  Fig.  2. 
Make  the  drawing  the  same  size  as  the  figure. 

1  By  color  value  is  meant  the  degree  of  lightness  or  darkness  due  to  the  actual  color  (the 
local  tone)  of  the  object.  If  students  are  at  all  uncertain  of  the  meaning  of  this,  they  are 
advised  to  chocse  the  line  drawing  from  Fig.  1. 


rrms  examination  is  continued  on  page  2) 

72 


Page  2 


Fig.  1 
(THIS  EXAMINATION   IS  CONTINUED  ON    PAGE  3) 


73 


rage  3 


Fig.  2 


74 


Page  1 

DRAWING— FREE-HAND 


Saturday,  June  26 


1920 

9  a.m.     Two  hours 


Candidates  must  do  all  exercises. 

An  incomplete  drawing,  correctly  laid  out  and  executed  by  correct  method,  is  better 
evidence  of  proficiency  than  a  completed  drawing,  incorrect  in  construction  or  slovenly 
in  execution. 

All  work  must  be  strictly  free-hand  work  without  assistance  from  measuring  slips, 
instruments,  or  artificial  aids  of  any  kind. 

1.  a)  At  what  institution  did  you  receive  your  training  in  drawing  for  this 

examination  ? 
b)  Over  how  many  years  did  this  training  extend  ? 

2.  Make  a  Hne  drawing  in  perspective  of  the  bench  and  the  cyhndrical  barrel 

shown  in  elevation  in  Fig.  i,  arranged  as  shown  in  plan  in  Fig.  2. 


Fig.  I 


Fig.  2 


Have  the  eye  level  slightly  above  the  top  of  the  barrel. 
Do  not  show  thicknesses. 

Using  light  lines,  draw  the  horizon  line  and  all  construction  lines  which  indi- 
cate the  positions  of  vanishing  points. 
Make  the  drawing  not  less  than  four  inches  in  width. 

3.  What  is  meant  in  perspective  by  the  terms  picture  plane  and  horizon  line? 

4.  Make  either  a  drawing  in  line  only  from  Fig.  4,  or  a  drawing  in  light  and  shade, 

without  regard  to  color  value,  from  Fig.  3. 
Make  the  drawing  the  same  size  as  the  figure. 


(THIS  EXMINATION  IS  CONTINUED  ON  PAGES  2.  3,  AND  4) 


75 


, 


4M*y»k:* 


Vl^ 


77 


DRAWING  —  MECHANICAL 


79 


DRAWING— MECHANICAL 


1916 


Saturday 


9:00  a.m.     Two  hours 


1.  Draw  accurately  the  figures  for  the  following  constructions,  and  in  each  case 

indicate  clearly  on  the  figure  or  explain  briefly  the  method  used : 

a)  To  draw  two  intersecting  lines  making  with  each  other  an  angle  equal  to  that 

formed  by  two  given  intersecting  lines.  Draw  at  random  any  two  inter- 
secting lines  forming  an  angle  ABC,  with  the  side  BC  horizontal.  Else- 
where on  the  paper  lay  off  an  angle  A'B'C  equal  to  ABC,  with  the 
side  B'C  (drawn  at  random)  inclined  at  any  unknown  angle  to  the 
horizontal. 

b)  To  draw  a  tangent  to  a  circle  from  a  point  outside  the  circle  by  geotnetric 

construction. 

c)  To  divide  a  right  angle  into  six  equal  parts,  using  only  the  triangles  and 

T-square. 

2.  Draw  a  parabola  passing  through  the  ends  of  a  vertical  line  3i  inches  long 

and  having  for  its  vertex  a  point  distant  2  inches  horizontally  from  the 
middle  point  of  the  line. 


1  1 

f 1 

-  Ir' 

K 

1      \ 

1 
1   1 

1      1 

Llj 

L,      . 

_J 

1 
1 

The  top,  front,  and  end  views  (horizontal,  vertical,  and  profile  projections)  of 
a  box  are  shown  above,  drawn  to  full  scale  (or  actual  size). 

a)  Does  the  hole  in  the  top  face  extend  through  the  face  into  the  interior  of  the 

box  ?     If  not,  how  deep  is  it  ? 

b)  Answer  the  same  cjuestion  as  to  the  hole  in  the  right-hand  end. 

c)  What  are  the  dimensions  of  the  groove  in  the  bottom  ? 

d)  What  are  the  dimensions  of  the  cleat  inside  the  box  at  the  left-hand  side  ? 


8o 


(SEE  NEXT  PAGE) 


A  right  pyramid,  whose  altitude  is  3  inches,  has  for  its  base  a  Ij-inch  square, 
two  opposite  sides  of  which  are  parallel  to  the  vertical  plane.  The  apex 
is  1  inch  behind  the  vertical  plane  and  2  inch  below  the  horizontal  plane. 
The  axis  is  parallel  to  the  vertical  plane  and  inclined  at  an  angle  of  60  degrees 
to  the  horizontal. 

a)  Draw  the  horizontal  and  vertical  projections  of  the  pyramid. 

b)  Find  the  true  size  and  shape  of  the  section  cut  from  the  pyramid  by  a 

plane  parallel  to  the  vertical  plane  and  f  inch  behind  it. 


Description. — The  material  of  the  rack  shown  above  is  all  f  inch  thick  and  the 
rod  is  f  inch  in  diameter.  The  board  is  15  inches  long  and  4§  inches  wide. 
Each  bracket  is  made  from  a  piece  3  inches  long  and  2  inches  wide,  by  cut- 
ting off  the  two  corners  at  45  degrees,  as  shown.  The  hole  is  in  the  center 
of  the  bracket.  Each  bracket  is  screwed  to  the  board  symmetrically,  the 
nearest  edge  being  §  inch  from  the  end  of  the  board. 

Problem. — Make  a  working  drawing  of  the  rack  shown  above.  Include  a 
top  view,  a  front  view,  and  an  end  view,  using  a  scale  of  \  inch  to  1  inch 
(j  actual  size).  Put  on  all  necessary  dimensions.  Using  some  simple 
single-stroke  free-hand  lettering,  print  carefully  a  title  (Towel  Rack),  and 
such  brief  notes  as  will  inform  the  workman  what  materials  are  to  be  used, 
how  they  are  to  be  fastened  together,  and  what  finish  you  would  suggest  for 
the  surfaces. 

6.  A  right  cylinder,  Ij  inches  in  diameter,  whose  axis  is  2  inches  long  and 
vertical,  stands  at  the  center  of  the  upper  face  of  a  block  \h  inches  wide, 
1|  inches  deep,  and  2  inches  high.  The  cylinder  is  cut  by  a  plane  which 
passes  through  its  axis  parallel  to  the  front  face  of  the  block  and  the  half 
of  the  cylinder  in  front  of  the  plane  is  removed.  INIake  an  isometric  draw- 
ing of  the  block  and  the  remaining  half  of  the  cylinder. 


DRAWING— MECHANICAL 


Saturday 


1917 


9  a.m.    Two  hours 


1.  Illustrate  the  following  geometric  constructions  by  means  of  accurately  drawn 

figures.  Where  the  method  is  not  clearly  evident  from  the  figure,  add  a 
brief  explanation. 

a)  To  bisect  a  given  arc. 

b)  To  construct  half  of  a  true  ellipse  whose  axes  are  3  inches  and  4  inches 

respectively.     Sketch  the  curve  neatly  free-hand  through  the  points 
obtained. 

2.  Make  an  isometric  drawing  of  a  rectangular  block  3  inches  long,  2  inches  wide 

and  1|  inches  high,  with  a  right  pyramid  1^  inches  high  resting  centrally 
on  the  top  face  of  the  block.  The  base  of  the  pyramid  is  a  hexagon  each 
side  of  which  is  f  inch  long;  two  sides  of  the  hexagon  are  parallel  to  the  long 
edges  of  the  prism.  Lengthwise  through  the  center  of  the  block  there  is  a 
circular  hole  Ij  inches  in  diameter. 

3.  Description. — The  material  of  the  bird  house  shown  below  is  all  5  inch  thick. 

The  house  is  8  inches  by  12  inches.  The  vertical  side  walls  are  6  inches 
high.    The  highest  point  of  the  roof  is  9  inches  above  the  floor.    There  is 


no  interior  framework.  The  roof  overhangs  at  the  sides  and  ends  2  inches 
(measured  horizontally).  A  circular  hole  2^  inches  in  diameter  extends 
through  each  end  half-way  between  the  sides.  The  center  of  each  hole  is 
2  inches  above  the  floor.  The  interior  is  divided  into  two  equal  com- 
partments by  a  vertical  partition  wall  parallel  to  the  ends  of  the  house. 

(SEE  NEXT  PAGE) 
82 


The  house  rests  centrally  on  a  plank  1  inch  thick,  14  inches  wide  by  18 
inches  long,  in  such  a  position  as  to  leave  a  space  3  inches  \\-ide  entirely 
around  it. 
Problem. — Make  a  working  drawing  of  the  bird  house  shown  on  page  i.   Include : 

a)  A  top  view,  a  front  view,  and  an  end  view,  drawn  to  a  scale  of  \  inch  to 

1  inch  (one-fourth  actual  size). 

b)  The  necessary  dimensions. 

c)  A  simple  title  (Bird  House),  and  such  brief  notes  as  will  inform  the  workman 

what  materials  are  to  be  used,  how  they  are  to  be  fastened  together,  and 
what  finish  you  would  suggest  for  the  surfaces.  Print  carefully,  using 
some  simple  single-stroke  free-hand  lettering. 

The  dimensions  of  the  wedge  shown  below  (in  isometric  i)rojection)  are  as 
follows:  The  larger  base  is  a  rectangle  1  inch  by  2  inches;  the  smaller  base 
is  a  rectangle  |  inch  by  2  inches;  the  vertical  distance  between  the  bases 
is  l\  inches.  The  ends  are  equal  and  parallel  trapezoids,  and  the  side 
faces  slope  equally. 


a)  Draw  the  horizontal  and  vertical  projections  (top  and  front  views)  of  the 

wedge  (actual  size)  in  the  follo^\^ng  position:  its  larger  base  is  uppermost 
and  \  inch  below  the  horizontal  plane  of  projection;  one  corner  of  this 
base  is  in  the  vertical  plane  of  projection,  and  the  longer  edges  of  the  base 
make  30  degrees  with  the  vertical  plane  of  projection. 

b)  Find  the  true  shape  of  the  section  cut  from  the  wedge  by  a  plane  which 

passes  through  its  exact  center.    The  cutting  plane  is  perpendicular  to 
the  horizontal  plane,  but  makes  60  degrees  with  the  longer  edges  of  the 
base  of  the  wedge  (30  degrees  with  the  vertical  plane). 
(SEE  NEXT  PAGE) 

83 


5.  a)  Enumerate  briefly  the  precautions  to  be  observed  in  the  use  of  the  ruling 

pen. 
b)  How  would  you  test  a  triangle  for  accuracy  ? 

6.  The  accompanying  full-size  drawing  shows  three  projections  of  a  1|  inch  cube 

from  which  three  cavities  have  been  cut.     State  the  length,  width,  and 
depth  of  each  cavity,  as  determined  by  direct  measurement  from  the  drawing. 


%^ 


1 

1 

1 

1 

H 


1918 


DRAWING— MECHANICAL 


Saturday,  June  22 


9  a.m.    Two  hours 


The  more  important  problems  have  been  placed  near  the  beginning  of  the  paper,  but 
if  the  two-hour  period  allowed  for  the  examination  is  apportioned  properly  between  the 
six  problems,  there  should  be  no  necessity  for  omitting  any. 

1.  Make  a  working  drawing  of  the  book-rack  shown  below.     Include: 

(a)  Three  views,  drawn  to  a  scale  of  one-eighth  actual  size. 

(b)  The  necessary  dimensions. 

(c)  Enough  brief  notes  to  describe  fully  the  materials,  fastenings,  and 

finish. 

(d)  A  title,  such  as  "  Design  for  a  Wooden  Book-rack." 

Description:  The  upright  ends  are  1  inch  thick,  10  inches  wide,  and  8  inches 
high,  with  upper  corners  beveled  2  inches  in  each  direction;  the  hole,  2^ 
inches  in  diameter,  is  centered  with  its  upper  edge  1  inch  below  the  upper 
edge  of  the  end  piece.  The  distance  in  the  clear  between  the  inner 
surfaces  of  the  two  upright  ends  is  23  inches.  The  rest  of  the  material 
is  1  inch  square;  the  two  long  side  pieces  are  each  28  inches  long,  and 
the  two  short  cross  pieces  are  each  14  inches  long.  The  ends  fold  down 
flat. 


Make  an  isometric  drawing  of  a  right  prism;  its  axis  is  vertical  and  2  inches 
long;  its  upper  and  lower  bases  are  equilateral  triangles  whose  sides  are 
3  inches  long.  A  cyHndrical  hole  1^  inches  in  diameter  extends  through 
the  prism  from  top  to  bottom;  the  axis  of  the  hole  coincides  with 
the  axis  of  the  prism.  (The  isometric  drawing  of  the  circle  may  be 
sketched  freehand  after  four  or  more  of  its  points  have  been  determined 
accurately.) 


(SEE  NEXT  PAGE) 


S5 


3.  Three  views  of  an  object  are  drawn  below. 

(a)  Is  1-2-3-4  ^^  opening  or  a  raised  part  ?    What  are  its  dimensions  ? 

(b)  Answer  the  same  two  questions  with  respect  to  5-6-7-8. 

(c)  Answer  the  same  two  questions  with  respect  to  A-B-C-D. 


/  a       1  , .  1 

4 

1                1 

1                1 

— '^            1 

AS 
DC 

1 
1 
1 
1 

1              1 
1              1 

r--\ 
____^_^_ I I 

-^ S 6_ 


1 

1 

1 

a 


The  front  view  and  the  end  view  of  a  soHd  are  shown  below.     Copy  these 

views  and 

{a)  Draw  the  top  view. 

(6)  Show  the  true  shape  of  the  section  cut  from  the  solid  by  a  vertical  plane 
which  intersects  the  axis  of  the  solid  at  a  point  equidistant  from  the 
ends  of  the  soUd,  and  is  inchned  at  60°  to  that  axis. 


[Solve  either  (c)  or  (6)] 

(fl)  Draw  two  regular  hexagons  each  1^  inches  on  a  side.     Use  a  different 

method  for  each.     One  method  must  be  that  in  which  only  the  T-square, 

triangles,  and  scale  are  used. 
(6)  Draw  the  end  view  and  the  front  view  of  a  helix  whose  axis  is  horizontal. 

The  diameter  of  the  helix  is  2  inches  and  the  pilch  is  3  inches.     Sketch 

the  curve  neatly  freehand  after  the  necessary  points  have  been  accurately 

determined. 


86 


(SEE  NEXT  PAGE) 


6.  (a)  One  view  of  an  object  is  shown  below;  no  other  views  need  be  considered. 
The  dimensions  given  are  numerically  correct.  Required  to  copy  the 
view,  and  to  place  the  dimensions  on  it  in  a  manner  that  will  conform  to 
standard  practice. 


» 


-% 


4^" 


CVj\ 


^'<^y 


(SEE  NEXT  PAGE) 


(&)  The  frustum  of  a  right  pyramid  rests  centrally  on  a  block  which  is  2  inches 
square  and  |  inch  high.  Two  side  faces  of  the  block  are  inclined  at  30° 
to  the  vertical  plane  of  projection  as  is  shown  in  the  accompanying 
vdews.  The  lower  base  of  the  frustum  is  1  inch  square,  with  each  side 
parallel  to  the  corresponding  edge  of  the  block;  the  upper  base  is  |  inch 
square;  the  height  of  the  frustum  is  1|  inches.  In  each  of  the  views  as 
shown  there  are  mistakes  and  omissions.  Required  to  make  a  correct 
sketch  of  each  view. 


88 


J 


Page  1 

DRAWING— MECHANICAL 


Saturday,  June  21 


1919 


9  a.m.    Two  hours 


Candidates  taking  the  examination  in  Mechanical  Drawing  are  requested  to  write 
their  neunes  in  addition  to  their  examination  numbers  on  the  answer  book  and  sheets  of 
drawing  paper  used  in  the  examination. 


1.  Make  a  working  drawing  of  the  ink-bottle  holder.     Include 

(a)  Three  views  drawn  to  a  scale  of  one-half  size. 

(b)  The  necessary  dimensions. 

(c)  A  brief  title,  giving  name  of  object,  scale,  date,  and  name. 

(d)  Complete  notes  describing  materials,  fastenings,  finish,  etc. 

Data: 
Base:  of  |-inch  stock,  4  by  6  inches. 

Bottle  block:  1  inch  thick,  2|  by  4|  inches.  Holes  If  inches  in  diameter 
and  1  inch  deep.     Space  AB  =  ^  inch. 

Penholder  strips:  §  inch  wide,  i  inch  deep,  2|  inches  long;  w-inch  radius 
at  end.  CD  =  ^  inch.  Diameter  of  semicircular  grooves  \  inch,  spaced 
evenly. 


(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


S9 


Page  2 

2.  [A  nswer  four  of  the  five] 

(a)  How  should  drawing  pencils  be  sharpened  ? 

(b)  Name  four  common  causes  of  blots  in  inking  due  to  improper  handling 

of  the  drawing  instruments. 

(c)  Describe  fully,  with  a  sketch,  the  method  of  drawing  a  line  inclined  at 

75  degrees  to  the  horizontal. 

(d)  In  what  order  should  the  hnes  of  a  drawing  be  inked  ? 

(e)  Why  and  when  and  how  much  should  the  legs  of  the  compasses  be  bent  ? 

3.  (a)  Draw  the  top,  front,  and  side  views  of  the  frustum  of  a  right  square 

pyramid.  Axis  vertical.  Sides  of  upper  base  f  inch,  of  lower  base 
2  inches;  vertical  distance  between  bases  2|  inches;  two  edges  of  each 
base  parallel  to  V. 

(b)  Show  the  true  shape  of  the  section  cut  from  the  above-mentioned  soUd 
by  a  plane  which  is  perpendicular  to  V,  makes  45  degrees  with  H,  and 
passes  through  the  middle  point  of  the  axis. 

4.  Make  an  isometric  drawing  of  the  following  block: 

Front  vertical  face  a  regular  hexagon,  sides  1  inch,  two  sides  horizontal. 
Rear  vertical  face  a  regular  hexagon,  sides  2  inches.  Axis  horizontal  and 
2|  inches  long.  Side  faces  all  equally  inclined  to  the  axis.  A  round  hole 
1|  inches  in  diameter  extends  through  the  block;  the  axis  of  the  hole 
coincides  with  the  axis  of  the  block. 


5. 


The  front  and  end  views  are  given.    Copy  these  and  draw  the  top  view. 


90 


(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  3) 


Page  3 


6. 


r:\~ 



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\y 

/ —  \ 





A 

The  object  represented  above  is  composed  of  several  blocks. 

(a)  Give  the  length  of  each  block  and  the  shape  of  its  cross-section. 

(b)  What  is  represented,  by  the  dashed  lines  at  the  top,  and  what  at  the 

bottom  of  the  vertical  block  ? 


91 


Page  1 

DRAWING— MECHANICAL 


Saturday,  June  26 


1920 


9  a.m.    Two  hours 


Candidates  taking  the  examination  in  Mechanical  Drawing  are  requested  to  write 
their  names  in  addition  to  their  examination  numbers  on  the  answer  book  and  sheets  of 
drawing  paper  used  in  the  examination. 


^^9 


1.  Make  a  full-size  isometric  drawing  of  the  soUd  shown  below. 


9- 


(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  9) 


Page  2 

Make  a  working  drawing  of  the  pen  tray.  Include  three  views  drawn  to  one- 
half  size;  all  necessary  dimensions;  brief  printed  notes  describing  materials, 
finish,  and  the  necessary  fastenings;  a  brief  printed  title,  "  Pen  Tray,"  scale, 
name,  and  date. 

Description.  Over  all  dimensions — length  8  inches,  width  3j  inches, 
height  2f  inches.  Material — all  \  inch  thick.  Base — 8  inches  by  2\  inches. 
Side  pieces — 1  inch  high;  length  on  top  3|  inches.  Upright  supports — 
2]  inches  square;  45°  bevels  begin  \  inch  from  each  end  and  cut  \  inch  deep; 
holes  1  inch  in  diameter  and  at  center  of  pieces;  supports  fold  outward. 


3.  a)  Write  the  following  sentences  and  supply  the  missing  expressions: 
The  scale  should  not  be  used  as because  — 


In  using  the  T-square  for  drawing  horizontal  lines,  always  place  its 

head  against  the side  of  the  drawing  board,  hold 

its with  the hand,  and  rule  along 

its edge  in  a  direction  from to 

h)  Circumscribe  a  circle  about  a  triangle  whose  sides  are  2,  3,  and  4  inches  long 
respectively.    Show  the  construction  lines. 

Given  a  2-inch  cube;  two  faces  are  horizontal;  its  vertical  (side)  faces  make 
45"  with  the  vertical  plane  of  projection  (7);  a  central  vertical  opening 
1  inch  square  extends  entirely  through  it. 

a)  Draw  the  top  view  and  the  front  view  of  the  cube. 

b)  The  cube  is  cut  by  a  plane  which  passes  through  its  center,  is  perpendicular 

to  the  vertical  plane  of  projection  (F);  and  is  inclined  at  30°  with  the 
horizontal  plane  of  projection  {11).  Required  the  true  shape  of  the 
section  cut. 


(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  3) 


93 


Page  3 

5.  Three  full-size  views  of  an  object  are  shown  below.     Answer  concisely  the 
following : 

a)  In  which  face  is  there  an  opening  and  how  large  is  it  ? 

b)  From  which  face  does  a  projection  extend?     Give  the  dimensions  of  the 

projection. 

c)  Which  face  contains  a  groove  ?     What  is  the  form  of  the  groove  and  what 

are  its  dimensions  ? 


i) 


94 


GEOGRAPHY 


95 


1916 
GEOGRAPHY 

Friday  9:00  a.m.    Two  hours 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  at  the 
time  of  the  examination. 

No  extra  credit  will  be  given  for  more  than  the  required  number  of  questions. 

Group  I 
(Answer  one  question  from  this  group.) 

1.  Explain  the  term  heat  equator.    How  does  its  position  vary  with  the  seasons  ? 

Why  is  it  an  irregular  line  ? 

2.  Draw  two  diagrams  showing  the  relations  of  the  sun's  rays  to  the  Northern 

Hemisphere  in  summer  and  in  winter. 

Group  II 
(Answer  one  question  from  this  group.) 

3.  Tropical  driftwood  is  brought  to  the  coast  of  Spain  by  ocean  currents.     From 

what  land  does  it  probably  come,  and  what  course  does  it  follow  ? 

4.  A  vessel  was  sunk  owing  to  collision  with  an  iceberg  during  a  fog  on  the 

Newfoundland  Banks.  What  caused  the  fog?  Where  did  the  iceberg 
come  from,  and  how  did  it  reach  the  Banks  ? 

Group  III 
(Answer  two  questions  from  this  group.) 

5.  Explain  the  difference  in  rainfall  (a)  between  the  east  and  west  slopes  of  the 

Andes  in  Peru  and  northern  Chile;  (b)  between  the  east  and  west  slopes 
of  fhe  Sierra  Nevadas  in  California;  (c)  between  the  northern  and 
southern  slopes  of  the  Himalayas. 

6.  What  facts  make  it  possible  to  predict  the  weather  in  the  eastern  United 

States  ?     Why  do  weather  predictions  sometimes  fail  ? 

7.  Explain  why  lowlands  under  the  trade  wind  belts  are  usually  deserts.    Name 

two  such  deserts. 

Group  IV 

(Answer  three  questions  from  this  group.) 

8.  Account  for  the  saltness  of  Great  Salt  Lake.     What  change  in  natural  condi- 

tions would  make  the  lake  fresh  ?  What  are  the  topographical  evidences 
of  past  changes  in  the  lake  level  ? 

9.  What  are  glacial  erratics  (foreign  boulders)  ?     Name  the  states  where  you 

would  e-xpect  to  find  them.  With  what  peculiarities  of  topography  are 
they  commonly  associated  ? 

(SEE  NEXT  PAGE) 


10.  Draw  a  profile  or  cross-section  of  a  plateau  in  a  young  stage  of  dissection. 

Draw  a  second  profile  or  cross-section  showing  the  same  region  maturely 
dissected;  and  a  third  showing  the  same  region  in  old  age. 

11.  Why  does  such  a  river  as  the  lower  Mississippi  make  a  poor  boundary  line? 

If  you  owned  a  plantation  bordering  such  a  river,  what  dangers  would 
threaten  your  property  ?  Would  you  rather  live  on  the  inside  or  the  out- 
side of  a  bend  in  the  river  ?     Why  ? 

12.  Define  ten  of  the  following  terms:   horse  latitudes,  drumlin,  talus,  solstice. 

neap  tide,  isotherm,  bore,  fiord,  monsoon,  ox-bow  lake,  anticyclone,  cre- 
vasse, fall-line,  residual  soil,  cirque. 


97 


1917 
GEOGRAPHY 

Friday  2  p.m.    Two  hours 

No  extra  credit  will  be  given  for  more  than  the  required  number  of  questions. 

Group  I 
(Anycver  one  question  from  this  group.) 

1.  What  differences  would  there  be  in  the  climate  of  the  earth  if  its  axis  were 

perpendicular  to  the  plane  of  its  orbit  ? 

2.  Draw  a  diagram  showing  the  relative  positions  of  earth,  moon,  and  sun  at 

the  times  of  spring  and  neap  tides  of  one  lunar  month. 

Group  II 
(Answer  one  question  from  this  group.) 

3.  Coral  reefs  are  absent  from  the  shores  of  the  Galapagos  Islands  which  lie 

under  the  equator  off  the  west  coast  of  South  America;  but  they  occur 
around  the  shores  of  the  Bermuda  Islands  32°  north  of  the  equator  off  the 
east  coast  of  North  America.     Explain  this  peculiarity  of  distribution. 

4.  Explain  the  chief  differences  between  the  topography  of  the  ocean  floor  and 

the  topography  of  the  land.  How  do  near-shore  deposits  differ  from  those 
of  the  deep  sea  ? 

Group  III 

(Answer  two  questions  from  this  group.) 

5.  The   eastern  and  western  sides  of  Lake  Michigan  have  unlike  climates. 

Which  side  is  the  more  favorable  for  fruit  raising  ?     Why  ? 

6.  Describe  two  types  of  barometers.    Explain  how  each  works.    For  what 

purposes  are  barometers  used  ? 

7.  With  the  accompanying  weather  map  for  the  morning  of  December  8,  1916, 

before  you,  predict  the  temperature,  wind  direction,  and  state  of  the  sky  at 
Columbus,  Ohio  (indicated  by  red  star  on  the  map),  for  the  afternoon  of 
the  8th  and  for  the  9th. 

Group  IV 

(Answer  three  questions  from  this  group.) 

8.  In  what  different  ways  are  lakes  commonly  produced  ?     Name  an  example 

of  each  kind  of  lake.  Through  what  processes  do  lakes  usually  become 
extinct  ? 

9.  How  are  alluvial  fans  formed  ?    In  what  part  of  the  United  States  are  they 

most  common  ?     Why  ?     What  use  does  man  make  of  them  ? 

10.  Describe  3  types  of  soils,  each  of  which  is  characteristic  of  a  particular 

region  of  the  United  States.  Explain  the  origin  of  each  type,  and  discuss 
its  value  for  agriculture. 

11.  Describe  the  different  types  of  land  forms  which  you  would  expect  to  find 

in  a  maturely  dissected  volcanic  region  and  explain  the  processes  by  which 
each  form  is  produced. 

12.  Define  ten  of  the  following  terms:    humus,  loam,  eolian  deposit,  cumulus 

cloud,  baselevel,  moraine,  water-table,  atoll,  playa,  till,  spit,  stalagmite. 


» 


1918 
GEOGRAPHY 

Friday,  June  21  2  p.m.     Two  hours 

No  extra  credit  will  be  given  for  more  than  the  required  number  of  questions. 

Group  I 
(Answer  one  question  from  this  group.) 

1.  If  the  earth's  axis  were  inclined  30  degrees  away  from  a  perpendicular  to 

the  plane  of  its  orbit,  what  would  be  (a)  the  latitude  of  the  Arctic  Circle, 
(b)  the  width  of  the  Temperate  zones,  (c)  the  width  of  the  Torrid  zone  ? 

2.  What  difference  is  there  in  the  positions  of  earth,  sun,  and  moon  during  full 

moon  and  during  a  total  eclipse  of  the  moon  ?  What  phenomenon  observ- 
able during  every  eclipse  of  the  moon  indicates  the  spherical  form  of 
the  earth? 

Group  II 
{Answer  one  question  from  this  group.) 

3.  Account  for  the  fact  that  the  water  at  the  bottom  of  the  Gulf  of  Mexico  has  a 

temperature  about  4°  F.  higher  than  the  water  of  the  adjacent  open  ocean 
in  the  same  latitude  at  the  same  depth.  Name  another  body  of  water 
connected  with  the  ocean  that  exhibits  a  similar  phenomenon. 

4.  Why  is  the  harbor  of  Hammerfest,  Norway,  76°  N.,  not  closed  by  ice  in 

winter  ?  Why  would  it  probably  be  closed  by  ice  if  the  continent  of  South 
America  were  shifted  8°  farther  north  ? 


Group  III 
{Answer  two  questions  from  this  group.) 

5.  State  two  places  in  the  Northern  Hemisphere  where  the  isotherm  of  40°  F. 

bends  distinctly  to  the  north,  and  two  places  where  it  bends  distinctly  to 
the  south,  on  the  isothermal  chart  of  the  world  for  January.  Give  the 
reason  in  each  case. 

6.  What  atmospheric  conditions  are  responsible  for  such  disastrous  inundations 

of  low  coasts  as  occurred  at  Galveston,  Texas,  in  the  fall  of  1900  ? 

7.  What  are  the  causes  that  determine  the  directions  of  (a)  the  trade  winds, 

{b)  the  prevailing  westerlies  ? 


(SEE  NEXT  PAGE)  ^ 

y9 


Group  IV 
{Answer  three  questions  from  this  group.) 

8.  Name  three  cities  the  locations  of  which  have  been  deternained  by  distinctly- 

different  topographic  features,  and  explain  how  these  features  were  effective 
in  each  case. 

9.  Name  the  different  types  of  moraines  and  explain  how  each  is  formed. 

10.  Describe  the  significant  characteristics  and  give  your  understanding  of  the 
history  of  each  of  the  valleys  shown  in  the  accompanying  diagrams: 


11.  Draw  a  contour  map  of  an  alluvial  fan,  showing  characteristic  arrangement 

of  channels  on  the  surface  of  the  fan.     Draw  a  cross-section  of  the  fan, 
showing  location  of  coarsest  and  finest  deposits. 

12.  Define  ten  of  the  following  terms:  loess,  anticyclone,  sink-hole,  isobar,  spring 

tide,  cut-off,  bad  lands,  nimbus  cloud,  wind-gap,  peneplain,  aggradation, 
atoll. 


Page  1 

1919 
GEOGRAPHY 

Friday,  June  20  2  p.m.     Two  hours 

No  extra  credit  will  be  given  for  more  than  the  required  number  of  questions. 

Group  I 

{Answer  one  question  from  this  group.) 

1.  (a)  Define  map  projection.     (6)  Make  a  sketch  of  the  parallels  and  meridians 

as  they  are  in  a  Mercator's  projection  map  of  the  world,  (c)  Mention  the 
advantages  and  disadvantages  of  this  kind  of  map. 

2.  In  the  South  Temperate  zone  a  farm  on  a  hillside  sloping  north  can  grow 

earlier  spring  vegetables  than  a  farm  situated  on  level  land  at  the  base  of 
the  hill.     Why  is  this  true  ? 

3.  (a)  How  was  the  so-called  "daylight-saving"  in  summer  accomplished  by  the 

plan  practised  in  1918  ?     (b)  Why  will  this  scheme  not  work  in  winter  ? 

Group  II 
(Answer  one  question  from  this  group.) 

4.  If  the  master  of  a  sailing  ship  wished  to  take  advantage  of  ocean  currents 

and  prevailing  winds,  what  course  would  he  take,  and  why,  on  voyages 
(a)  from  Liverpool  to  Rio  de  Janeiro  and  (b)  from  Cape  Horn  to  Cape  of 
Good  Hope  ? 

5.  (a)  Where  and  how  do  the  icebergs  encountered  in  the  steamer  lanes  of  the 

North  Atlantic  originate  ?     (b)  Why  do  these  icebergs  float  so  far  south  ? 

(c)  Why  is  it  dangerous  for  a  large  ship  to  run  into  one  of  these  bergs  at 
high  speed  even  if  the  berg  rises  only  a  few  feet  above  the  surface  of  the 
sea  and  is  not  apparently  of  great  areal  extent  ? 

Group  III 
(Answer  two  questions  from  this  group.) 

6.  (a)  Draw  an  outline  map  of  the  part  of  the  earth's  surface  within  the  Tropics, 

and  on  it  indicate  and  label:  (1)  the  equator,  (2)  the  heat  equator  in  July, 
(3)  the  heat  equator  in  January,  {b)  On  the  same  map  locate  the  Sahara 
Desert  and  account  for  its  position. 

7.  The  daily  United  States  weather  map  for  a  certain  day  gave  the  pressure  for 

Denver,  Colorado,  as  30.00  inches.  Denver  is  one  mile  above  sea-level. 
What  was  the  actual  reading  of  the  barometer  at  Denver  on  that  day  ? 
Show  how  }'ou  obtain  your  result. 

8.  Distinguish  between  a  temperate-latitude  cyclone  and  a  temperate-latitude 

tornado  as  to  (a)  place  of  occurrence,  (b)  diameter,  (t)  destructiveness, 

(d)  climatic  effects. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

Group  IV 

(Answer  three  questions  from  this  group.) 

9.  Describe  as  a  whole  the  region  represented  on  the  accompanying  contour 
map,  mentioning  especially  the  different  forms  of  relief  and  the  drainage. 
State  {a)  the  greatest  elevation,  {h)  the  least  elevation,  (c)  the  location  of 
the  steepest  slope.  Name  and  locate  the  works  of  man  indicated  on  this 
map  and  show  how  their  location  is  related  to  topography. 


10.  Describe  the  coastal  plain  of  Eastern  United  States  as  to  (a)  origin,  (6)  slope, 

(c)  drainage,  {d)  soil,  (e)  industries  and  their  location. 

11.  Give  an  account,  in  proper  notebook  form,  of  a  class  trip  taken  with  your 

teacher,  on  which  you  studied  (a)  stream  work,  or  {b)  rock  classes  and 
structures,  or  (c)  glaciation,  or  {d)  wind  work. 

12.  Give  reasons  why  Iowa  has  become  known  as  the  typical  agricultural  state 

on  account  of  (a)  its  topography,  {h)  its  original  vegetation  cover,  (c)  origin, 
composition,  texture,  and  depth  of  its  soils,  and  {d)  its  location. 

13.  Define  ten  of  the  following:    agonic  line;    mean  solar  time;    chronometer; 

erratic  bowlder;    nunatak;    monadnock;    cirque;    spit;    isotherm;    reUef; 
hanging  valley;   rejuvenation;   fault-scarp. 


Page  1 

1920 
GEOGRAPHY 

Friday,  June  25  2  p.m.     Two  hours 

No  extra  credit  will  be  given  for  more  than  the  required  number  of  questions. 

Group  I 
(Answer  one  question  from  this  group.) 

1.  How  do  the  lengths  (in  miles)  of  the  degrees  of  latitude  and  of  longitude  vary 

and  why  ?     Describe  one  method  of  determining  latitude ;   one  method  of 
determining  longitude. 

2.  If  a  man  is  standing  on  the  equator  at  noon  on  June  21,  in  what  part  of 

the  sky  (compass  direction)  will  he  see  the  sun?     How  many  degrees 
above  the  horizon  will  the  sun  appear  at  that  time  and  place  ? 

Group  II 
{Answer  one  question  from  this  group.) 

3.  Name  the  important  movements  of  the  ocean  waters  and  state  the  cause  or 

causes  of  each. 

4.  Give  five  characteristics  of  naturally  good  harbors  and  explain  how  the  lack 

of  each  might  affect  the  use  of  a  harbor. 

Group  III 
(Answer  two  questions  from  this  group.) 

5.  Distinguish  between  oceanic  and  continental  climates,  giving  characteristics 

of  each;  and  name  important  cities  where  each  is  typically  developed. 

6.  Why  are  there  two  rainy  seasons  in  the  equatorial  forests  of  Africa  and  no 

rainy  season  in  the  Sahara  Desert  ? 

7.  Explain  why  low-pressure  areas  in  the  prevailing  westerlies   usually  bring 

cloudy  or  rainy  weather.     Describe  and  explain  the  temperature  changes 
which  occur  at  a  given  point  while  the  center  of  a  low  is  passing  north  of  it. 

Group  IV 
(Answer  three  questions  from  this  group.) 

'8.  Write  an  essay  of  about  one  hundred  words  in  which  each  of  the  following 
terms  is  used  in  its  geographic  sense:  monadnock;  entrenched  (or  incised) 
meanders; '  residual  soil;  peneplain;  sluggish  rivers;  rejuvenation;  base 
level. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

9.  Describe  and  explain  the  geographic  features  observed  by  you  while  on  a 
field  trip  with  your  geography  teacher.  State  exactly  when  and  where  the 
trip  was  made. 

10.  A  road  having  a  west  to  east  direction  for  three  miles  crosses  over  a  north- 

south  ridge  which  is  one  hundred  feet  high  and  steep  near  the  top.  The 
road  then  turns  abruptly  to  the  north  and  follows  down  a  valley  bottom 
for  three  miles  beside  a  stream  which  falls  40  feet  to  the  mile.  Make  a 
contour  map  of  the  road  and  region  described,  on  a  scale  of  one  inch  to  the 
mile  and  with  a  contour  interval  of  20  feet. 

11.  Explain  the  relation  of  wells,  lakes,  permanent  streams,  and  temporary 

streams  to  the  water-table  or  ground-water  level. 

12.  Define  ten  of  the  following:    relative  humidity;    equinox;    mesa;    neve; 

geographic  cycle;  international  date  line;  metamorphic  rock;  differential 
weathering;  continental  shelf;  drumhn;  fjord;  feldspar. 


€1 

! 

5 


104 


PHYSICS 


i05 


1916 
PHYSICS 

Friday  9:00  a.m.    Two  hours 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  part 
of  the  examination.  ^ 

Answer  ten  questions  as  indicated  below.     No  extra  credit  will  be  given  for  more  %i 

than  ten  questions. 

Group  I 
(Omit  one  question  from  this  group.) 

1.  Define  density  and  specific  gravity.    How  do  they  compare  in  value  in  the 

metric  system  ?    How  do  they  compare  in  value  in  the  EngHsh  system  ? 

2.  Upon  a  table  stands  a  closed  cubical  box,  measuring  15  cm.  on  each  inside  edge, 

above  the  top  of  which  projects  a  tube  20  cm.  high  and  1  sq.  cm.  in  area 

of  inside  cross-section.     The  box  and  tube  weigh  200  gms.     Both  box  and 

tube  are  filled  with  water.     Find 

(a)  the  total  force  exerted  upon  the  table; 

{b)  the  total  force  exerted  by  the  water  upon  the  bottom  of  the  box. 

3.  When  supplied  with  100  cubic  feet  of  water  per  second,  at  a  head  of  45  feet, 

what  horse-power  is  developed  by  a  turbine  water  wheel  having  an  effi- 
ciency of  80  per  cent?     (One  cubic  foot  of  water  weighs  62.4  pounds.) 

4.  A  trolley  car  starting  from  rest  experiences  a  uniform  acceleration.    At 

the  end  of  20  seconds  its  speed  is  15  miles  per  hour, 
(a)  What  is  its  acceleration  ? 
{b)  How  far  has  it  traveled  ? 

c 

Group  II 

{Omit  one  question  from  this  group.) 

5.  Given  a  gun,  a  stop  watch,  and  a  thermometer,  how  could  the  width  of  a 

lake  be  determined  ?    Show  how  the  calculations  should  be  performed. 

6.  If  two  musical  tones,  one  of  68  vibrations  per  second  and  the  other  of  70 

vibrations  per  second,  are  sounded  at  the  same  time,  describe  and  explain 
the  effect  produced.     What  name  is  given  to  this  phenomenon  ? 

Group  III 
{Omit  one  question  from  this  group.) 

7.  Describe  an  experiment,  preferably  one  which  you  have  personally  per- 

formed, by  which  the  heat  changes  occurring  during  a  change  of  state, 
such  as  from  a  liquid  to  a  solid,  may  be  shown.  Explain  the  results 
obtained. 

8.  A  steel  projectile  is  moving  with  a  speed  of  700  meters  per  second  at  the 

instant  that  it  strikes  a  target.  Assuming  that  all  of  the  energy  of  motion 
is  transformed  into  heat  in  the  projectile,  calculate  its  rise  of  temperature. 
Take  the  specific  heat  of  steel  as  0 .  12  and  the  mechanical  equivalent  of 
heat  as  41,800,000  ergs.  *» 

9.  The  air  in  an  automobile  tire  has  a  pressure  of  80  pounds  per  square  inch  at 

a  temperature  of  15°C.  If,  after  the  car  has  been  driven,  the  temperature 
of  the  air  in  the  tire  has  risen  to  32°  C.,  what  is  the  air  pressure  in  the  tire  ? 

(SEE  NEXT  PAGE) 
io6 


Group  IV 
(Omit  one  question  from  this  group.) 

10.  Show,  by  means  of  a  diagram,  the  least  height  of  a  vertical  plane  mirror  which 

would  enable  a  man  6  ft.  tall  to  see  a  full  length  image  of  himself. 
Why  does  a  shallow  pond,  when  viewed  from  one  side,  appear  to  be  less 
deep  than  it  really  is  ? 

11.  If  the  illumination  necessary  for  reading  is  2  foot-candles,  how  far  away 

from  a  reader  may  a  16  candle-power  lamp  be  placed  ?  (One  foot-candle 
is  defined  as  the  intensity  of  illumination  produced  by  a  source  of  light 
of  one  candle-power  at  a  distance  of  one  foot  from  that  source,  the  light 
falling  perpendicularly.) 

12.  An  object  6  in.  long  is  placed  20  in.  in  front  of  a  concave  mirror  whose  radius 

of  curvature  is  2  ft. 

(a)  Where,  and  at  what  distance  from  the  mirror,  is  the  image  ? 

(b)  What  is  the  length  of  the  image  ? 

Group  V 
{Omit  one  question  from  this  group.) 

13.  Why  are  high  potential  currents  employed  for  the  long  distance  transmission 

of  electrical  energy  ?  Explain  the  use  of  transformers  as  employed  on 
transmission  circuits. 

14.  Given  three  1 10- volt  incandescent  lamps,  each  requiring  0 . 5  ampere.     Find 

the  voltage  required,  the  resistance  of  the  circuit  and  the  current  in  the 
circuit. 

(a)  when  the  lamps  are  connected  in  series; 

(b)  when  the  lamps  are  connected  in  parallel. 

15.  An  electric  heater  connected  to  a  110-volt  circuit  takes  600  watts.     How 

many  calories  of  heat  does  it  develop  in  10  minutes  ? 


107 


1917 
PHYSICS 

Friday  2  p.m.    Two  hours 

Answer  ten  questions  as  indicated  below.  No  extra  credit  will  be  given  for  more 
than  ten  questions.  Indicate  clearly  your  reasoning  in  each  problem  and  state  the  imits 
in  which  each  answer  is  expressed. 

Group  I 

(Omit  one  question  from  this  group.) 

1.  State  Archimedes'  principle.     Describe  an  experimental  proof  of  this  principle. 

Good  eggs  sink  and  bad  eggs  float  in  pure  water,  though  the  dimensions  of 
the  eggs  do  not  change.     Explain. 

2.  A  child  weighing  75  pounds  sits  in  a  swing.    The  swing  is  drawn  aside  and 

held  in  equihbrium  by  a  horizontal  force  of  30  pounds.  Find  the  tension 
in  each  of  tlie  two  ropes  of  the  swing. 

3.  An  automobile  tire  contains  an  inner  tube,  initially  empty,  the  capacity 

of  which  is  750  cubic  inches.  A  pump,  which  takes  in  at  each  stroke  30 
cubic  inches  of  air  at  a  pressure  of  15  pounds  per  square  inch,  is  employed 
to  pump  up  the  tire.  Assuming  no  change  in  temperature,  what  is  the 
air  pressure  in  the  tire  after  135  strokes  of  the  pump  ? 

4.  A  rifle  weighing  8.7  pounds  discharges  a  bullet  weighing  0.32  ounce  with  a 

velocity  of  2,700  feet  per  second. 

(a)  What  is  the  kinetic  energy  of  the  bullet  ? 

Q))  With  what  velocity  does  the  gun  recoil  ? 

Group  II 
{Omit  one  question  from  this  group.) 

5.  What  are  the  nature  and  the  direction  of  the  motions  of  a  small  portion  of  a 

medium  which  is  transmitting  sound? 
A  vibrating  tuning  fork  held  vertically  near  the  ear  is  slowly  rotated  about 
its  shank  as  an  axis.     State  and  explain  the  effects  observed. 

6.  What  is  the  length  of  a  pipe,  closed  at  one  end,  which  at  0°C.  will  give  the 

greatest  reinforcement  to  the  sound  of  a  tuning  fork  making  250  vibrations 
per  second  ? 

Group  III 

{Omit  one  question  from  this  group.) 

7.  Describe  two  experiments  which  indicate  that  heat  is  a  form  of    energy. 

What  causes  the  draught  of  a  chimney  ? 

8.  A  30-foot  steel  rail,  when  subjected  to  a  change  in  temperature  from  —  14°C. 

in  winter  to  36°C.  in  summer,  changes  0.0195  foot  in  length.  Find  the 
coefficient  of  linear  expansion  of  steel. 

(SEE  NEXT  PAGE) 
lod 


9.  A  glass  pitcher  weighing  1,500  grams  contains  1,800  grams  of  tea  at  40^0. 
Ice  is  used  to  cool  the  tea  to  10°C.  If  the  specific  heat  of  tea  is  1  and 
that  of  glass  is  0.18,  find  how  many  grams  of  ice  are  needed. 

Group  IV 
(Omit  one  question  from  this  group.) 

10.  Draw  a  diagram  of  a  compound  microscope  showing  the  lenses  used,  their 

focal  points,  and   the  locations  of   the   images  formed;  also   state   the 
character  (real  or  virtual)  of  each  image. 
The  critical  angle  for  water  is  48.5  degrees.    Show  by  a  diagram  what  is 
meant  by  this  statement. 

11.  The  image  of  a  post  12  feet  high  and  20  feet  from  a  camera  is  5  inches  long. 

(a)  How  far  from  the  lens  is  the  image  ? 

(b)  What  is  the  focal  length  of  the  lens  ? 

12.  What  is  the  cause  of  the  apparent  color  of  opaque  objects  ? 
Explain  why  a  mixture  of  yellow  and  blue  pigments  appears  green. 

Why  is  it  difficult  to  match  certain  colors  by  lamp-light  so  that  they  will  agree 
by  daylight  ? 

Group  V 

(Omit  one  question  from  this  group.) 

13.  A  man  holding  a  compass  under  the  trolley  wire  of  an  electric  railway  running 

north  and  south  observes  that  the  compass  needle  deflects  toward  the 
northwest.  What  can  you  infer  from  this  with  regard  to  the  current  in  the 
trolley  wire  ? 

A  single  loop  of  wire  lies  in  a  horizontal  plane  and  through  it  is  dropped  a 
bar  magnet  whose  north  pole  is  pointing  downward.  What  is  the  direction 
of  the  current  induced  in  the  wire  while  the  magnet  is  approaching  the 
loop  ?    What  factors  determine  the  magnitude  of  this  current  ? 

Describe  an  experiment  by  which  an  induced  current  may  be  produced  by 
moving  a  wire  forming  a  part  of  a  closed  circuit  in  the  earth's  magnetic  field. 

14.  In  a  copper  refinery  a  current  of  1,000  amperes  is  employed  in  a  plating  bath 

to  deposit  the  metal  by  electrolysis.     How  much  copper  is  deposited  in 
24  hours  ? 
(The  electrochemical  equivalent  of  copper  is  0.0(K)329  grams  per  coulomb.) 

15.  An  electric  bell  of  resistance  4.2  ohms  is  connected  by  a  wire  of  1.2  ohms 

resistance  to  three  dry  cells,  each  of  resistance  0 . 2  ohm  and  electromotive 
force  1.4  volts. 
What  current  flows  through  the  bell — 

(a)  When  the  cells  are  connected  in  series  ? 

(b)  When  the  cells  are  coimected  in  parallel  ? 

Show  by  a  diagram  how  the  cells  are  connected  in  each  case. 

109 


1918 
PHYSICS 

Friday,  June  21  2  p.m.    Two  hours 

Answer  ten  questions  as  indicated  below.  No  extra  credit  will  be  given  for  more 
than  ten  questions.  Indicate  clearly  your  reasoning  in  each  problem  and  state  the  units 
in  which  each  answer  is  expressed. 

Group  I 
{Omit  one  question  from  this  group.) 

1.  (a)  Explain  the  meaning  of  the  terms  acceleration,  work,  power,  momentum, 

moment  of  a  force. 
(b)  A  balance  has  unequal  arms,  the  left-hand  arm  having  a  length  99  per 
cent  of  that  of  the  right-hand  arm.    A  dealer  has  the  habit  of  putting 
in  the  left-hand  pan  the  articles  which  he  sells.     Who  gains,  the  dealer 
or  the  customer  ?    Why  ? 

2.  The  water  passing  through  the  turbine  water  wheels  at  the  Niagara  power 

plant  has  fallen  136  feet.  The  average  horse-power  of  the  turbines  is  5,000 
and  their  efficiency  is  85  per  cent.  How  many  cubic  feet  of  water  does 
each  turbine  discharge  per  minute?  (One  cubic  foot  of  water  weighs 
62 . 4  pounds.) 

3.  A  painter's  platform  is  18  feet  long  and  weighs  100  pounds.     Its  center  of 

gravity  is  8 . 5  feet  from  the  right-hand  end.  The  platform  is  hung  in  a 
horizontal  position  by  two  ropes,  one  attached  one  foot  from  one  end,  the 
other  one  foot  from  the  other  end.  When  a  painter  weighing  150  pounds 
stands  at  a  point  7  feet  from  the  left-hand  end  of  the  platform,  what 
weight  does  each  rope  support  ? 

4.  An  aeroplane  one  mile  above  the  earth  is  moving  horizontally  with  a  velocity 

of  60  miles  per  hour.  A  bomb  is  dropped  from  it  in  an  attempt  to  hit  a 
station.  When  the  bomb  is  released,  how  far  should  the  aeroplane  be 
from  the  point  ahead  in  its  path  which  is  directly  over  the  station  ? 


Group  II 
(Omit  one  question  from  this  group.) 

6.  Describe  an  experiment,  preferably  one  which  you  have  personally  performed, 
by  which  the  wave-length  of  a  musical  sound  may  be  determined. 

6.  A  man  is  standing  two  miles  in  front  of  a  cliff.  A  gun,  located  between  the 
man  and  the  cUff ,  is  fired.  The  man  hears  the  report  of  the  gun  and,  four 
seconds  later,  hears  the  echo  of  the  report  from  the  cliff.  Taking  the 
temperature  of  the  air  as  0°  C.,  fmd  the  distance  from  the  gun  to  the  cliff. 

(SEE  NEXT  PAGE) 


Group  III 

iPmit  one  question  from  this  group.) 

7.  Describe  an  experimental  method  of  determining  the  coefficient  of  expansion 
of  a  gas  under  constant  pressure. 

8  A  Centigrade  mercury  thermometer  contains  in  its  bulb  and  capillary  tube 
up  to  the  0°  mark  0 .  15  cubic  centimeter  of  mercury.  If  the  diameter  of 
the  capillary  tube  is  0.012 centimeter,  what  is  the  length  of  the  tube  from 
the  0°  mark  to  the  100°  mark  ?  (The  coefficient  of  apparent  expansion  of 
mercury  in  glass  is  0.00015G.) 

9.  How  many  kilograms  of  coal  would  be  needed  in  a  boiler  having  an  efficiency 
of  65  per  cent  to  convert  50  kilograms  of  water  at  10°  C.  into  steam  at 
100°  C.  ?  Assume  that  the  heat  value  of  the  coal  is  7,000  calories  per 
gram. 

Group  IV 
(Omit  one  question  from  this  group.) 

10.  (a)  Explain  in  terms  of  the  wave  theory  of  light  the  production  of  a  spectrum 

by  means  of  a  prism. 
(b)  Describe  the  appearance  of  the  solar  spectrum. 

11.  (a)  Describe  an  experimental  method  of  determining  the  index  of  refraction 

of  glass. 
(6)  The  index  of  refraction  of  glass  being  1.5,  find  the  speed  of  light  in  it. 

12.  The  works  of  a  watch  are  held  1 . 5  inches  from  a  jeweler's  eye-lens  which  has 

a  focal  length  of  1 .  75  inches.     How  many  times  are  the  works  magnified  ? 

Group  V 
(Omit  one  question  from  this  group.) 

13.  Using  diagrams  describe  an  electric  telephone  transmitter  and  an  electric 

telephone  receiver  and  explain  the  action  of  each. 

14.  A  total  current  of  24  amperes  flows  through  two  branches  of  a  divided  circuit 

having  resistances  of  7  and  5  ohms,  respectively.    Find 

(a)  The  strength  of  current  which  flows  through  each  branch. 

(b)  The  electromotive  force  required  to  maintain  the  current. 

15.  An  electric  motor  having  an  efficiency  of  85  per  cent  develops  8  horse-power 

when  connected  to  a  220-volt  circuit.     How  much  current  flows  through 
the  motor  ?      (One  horse  power  =  746  watts.) 


Page  1 

1919 
PHYSICS 

Friday,  June  20  2  p.m.    Two  hours 

Answer  ten  questions  as  indicated  below.  No  extra  credit  will  be  given  for  more 
than  ten  questions.  Indicate  clearly  yoiu:  reasoning  in  each  problem  and  state  the  units 
in  which  each  answer  is  expressed. 

Group  I 
(Omit  one  question  from  this  group.) 

1.  A  receiver  contains  500  cubic  centimeters  of  air  under  a  pressure  of  75  centi- 

meters of  mercury.  What  will  be  the  pressure  of  the  air  if  its  volume  is 
reduced  to  200  cubic  centimeters,  the  temperature  remaining  unchanged  ? 

2.  (a)  State  Pascal's  principle. 

(b)  A  submarine  weighs  1800  tons  when  its  submerging  tanks  are  empty, 

and  in  that  condition  10  per  cent  by  volume  of  the  submarine  is  above 
water.  What  weight  of  water  must  be  let  into  the  tanks  just  to  sub- 
merge the  boat  ? 

(c)  If  the  specific  gravity  of  sea-water  is  1.03,  what  volume  of  water  is 

required  to  submerge  the  boat  ? 

3.  (a)  Explain  the  meaning  of  these  terms:   moment  of  force;  acceleration; 

a  unit  of  force. 

(b)  Show  how  to  find  by  a  graphical  method  the  resultant  of  two  forces 
acting  at  an  angle  to  each  other. 

4.  A  uniform  plank  20  feet  long,  weighing  200  pounds,  rests  on  a  flat  roof  with 

8  feet  of  its  length  projecting  beyond  the  edge  of  the  roof.  If  a  keg  of 
nails  weighing  50  pounds  rests  over  a  point  1  ft.  from  the  inner  end,  how 
far  out  on  the  plank  beyond  the  edge  of  the  roof  may  a  man  weighing 
180  pounds  go  without  tipping  the  plank  ? 

Group  II 
(Omit  one  question  from  this  group.) 

5.  {a)  State  the  physical  difference  between  a  noise  and  a  musical  sound. 

[b]  Describe  briefly  an  experiment  that  demonstrates  which  characteristic 

of  a  musical  sound  determines  its  pitch. 

(c)  If  the  expansion  of  an  organ  pipe  is  ignored,  what  change,  if  any,  is  pro- 

duced in  the  sound  of  the  pipe  by  a  rise  in  temperature  ?  Give  reason 
for  your  answer. 

6.  Describe  some  common  form  of  resonator  and  explain  resonance  as  illus- 

trated by  its  action. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

Group  III 
{Omii  one  question  from  this  group.) 

7.  A  steel  tape  100  feet  long  and  correct  at  G0°  F.  is  used  for  measuring  a  base 

line  on  a  day  when  the  temperature  is  85°  F.  The  observed  length  is  330 
feet.  If  the  coefficient  of  linear  expansion  of  the  tape  is  0.0000058  per 
degree  Fahrenheit,  what  is  the  true  length  of  the  base  line  ? 

8.  (a)  Distinguish  between  temperature  and  quantity  of  heat. 

(b)  State  some  evidence  in  verification  of  the  statement  that  heat  is  a  form 

of  energy. 

(c)  Explain  what  is  meant  by  the  mechanical  equivalent  of  heat. 

9.  Two  hundred  grams  of  snow  at  0°  C.  are  contained  in  a  cup  the  thermal 

capacity  of  which  equals  that  of  12  grams  of  water.  Steam  at  a  tempera- 
ture of  100°  C.  is  turned  into  the  snow,  melting  it  and  raising  the  tempera- 
ture of  the  resulting  water  to  40°  C.  Assuming  no  loss  or  gain  of  heat, 
find  how  much  steam  is  used. 

Group  IV 
{Omit  one  question  from  this  group.) 

10.  (a)  Explain  carefully  all  that  will  happen  to  a  ray  of  sunlight  when  passed 

through  a  triangular  glass  prism. 
(b)  Why  does  a  green  leaf  appear  nearly  black  when  seen  in  a  red  light  ? 

11.  (a)  Describe  the  construction  and  use  of  some  form  of  photometer. 

(b)  A  16-candle-power  lamp  and  a  standard  candle  are  placed  5  feet  apart. 
At  what  position  between  them  should  a  screen  be  placed  that  its  two 
sides  may  be  equally  illuminated  ? 

12.  (a)  A  camera  has  a  lens  whose  focal  length  is  15  centimeters.     How  far  from 

the  lens  is  the  photographic  plate  when  there  is  focused  on  it  the  image 
of  an  object  300  centimeters  away  from  the  lens  ? 
(b)  If  the  image  is  10  centimeters  in  height,  what  is  the  height  of  the  object  ? 

Group  V 
{Omit  one  question  from  this  group.) 

13.  (a)  A  bar  magnet  is  broken  into  three  pieces  of  equal  length.     Describe  the 

magnetic  condition  of  these  pieces.     Illustrate  by  diagram. 
(6)  Describe  a  method  for  determining  the  sign  of  the  electrification  on  a 
charged  body. 

14.  A  small  arc  lamp  requires  a  current  of  5  amperes  and  a  difference  of  potential 

between  its  terminals  of  45  volts.  What  resistance  must  be  connected  in 
series  with  it  in  order  to  use  it  on  a  110- volt  circuit? 

15.  A  current  of  electricity  passed  through  a  coil  of  wire  hax'ing  a  resistance  of 

10  ohms  heated  1000  grams  of  water  from  15°  C.  to  61 .08°  C.  in  5  minutes. 
What  was  the  strength  of  the  current? 


Page  1 

1920 
PHYSICS 

Friday,  June  25  2  p.m.    Two  hours 

Answer  ten  questions  as  indicated  below.  No  extra  credit  will  be  given  for  more  than 
ten  questions. 

Indicate  clearly  your  reasoning  in  each  problem  and  state  the  units  in  which  each 
answer  is  expressed. 

Number  and  letter  each  answer  to  correspond  with  the  question  selected. 

Group  I 
(Omit  one  question  from  this  group.) 

1.  a)  Distinguish  between  mass  and  weight. 

h)  Could  the  fact  that  the  weight  of  a  body  changes  if  it  is  taken  from  the 
equatorial  to  the  polar  region  of  the  earth  be  shown  by  either  a  spring 
balance  or  a  beam  balance  ?    Explain. 

2.  A  body  having  a  volume  of  100  cubic  centimeters  and  a  density  of  2.5  is 

fastened  to  a  block  of  wood  having  a  volume  of  200  cubic  centimeters 
and  a  density  of  0.5. 

a)  What  will  the  combination  weigh  when  immersed  in  water  ? 

b)  What  will  the  combination  weigh  when  immersed  in  oil  of  density  0.9  ? 

3.  a)  Represent  by  a  diagram  a  system  of  pulleys  consisting  of  a  double  fixed 

block  and  a  single  movable  block. 
b)  If  the  efiiciency  of  the  above  system  is  70  per  cent,  how  great  a  weight 

can  be  lifted  by  a  force  of  30  pounds  apphed  to  the  free  end  of  the 
rope? 

4.  What  horse  power  is  required  to  run  an  automobile  on  a  level  road  at  the  rate 

of  30  miles  per  hour  if  the  forces  of  friction  amount  to  125  pounds  ? 

Group  II 

{Omit  one  question  from  this  group.) 

5.  a)  How  are  sounds  produced  and  how  are  they  transmitted  to  the  ear  ? 

b)  How  does  the  intensity  of  sound  vary  with  change  of  distance  from  the 
source  ? 

6.  a)  If  the  lowest  tone  which  the  ear  can  recognize  has  a  frequency  of  16 

vibrations  per  second  what  is  the  length  of  the  longest  wave  the  ear 
perceives  in  air  at  a  temperature  of  0°  C.  ? 

b)  What  effect,  if  any,  does  change  in  temperature  produce  in  the  velocity 
of  sound  in  air  ? 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 
114 


« 


Page  2 

Group  III 
(Omit  one  question  from  this  group.) 

7.  a)  Define  dew  point. 

h)  What  is  meant  by  the  relative  humidity  of  the  air  ? 

c)  How  may  the  relative  humidity  of  the  air  be  experimentally  determined  ? 

8.  If  gas  costing  $1 .00  per  1,000  cubic  feet  furnishes  GOO  B.T.U.  of  heat  per  cubic 

foot  of  gas  burned,  how  much  would  it  cost  to  raise  from  62°  F.  to  212°  F. 
one  quart  (2  pounds)  of  water  by  means  of  a  burner  and  kettle  having  a 
combined  efBciency  of  50  per  cent  ? 

9.  a)  Describe  in  detail  an  experimental  method  for  determining  the  specific 

heat  of  a  substance. 
h)  Explain  how  a  numerical  result  may  be  secured  from  the  data  obtained. 

Group  IV 
{Omit  one  question  from  this  group.) 

10.  In  a  darkened  room  a  spectrum  of  sunlight  is  thrown  on  a  screen.     A  bouquet 

of  red,  yellow,  and  blue  flowers  with  green  foliage  is  placed  in  the  red  end 
of  the  spectrum  and  gradually  moved  toward  the  violet  end.  State  and 
explain  what  would  be  observed. 

11.  a)  Describe  the  construction  and  explain  the  operation  of  the  so-called 

"pin-hole"  camera. 

b)  If  such  a  camera  is  8  inches  long  and  the  image  of  a  building  50  feet  high 
appears  as  an  image  3  inches  high  on  the  plate  how  far  away  is  the 
building  ? 

12.  a)  Represent  by  a  diagram  the  path  of  the  rays  of  light  through  the  lenses 

of  an  astronomical  telescope. 
b)  A  telescope  has  an  objective  whose  focal  length  is  30  feet  and  an  eye-piece 
whose  focal  length  is  1  inch.     What  is  the  magnifying  power  of  the 
telescope  ? 

Group  V 
(Omit  one  question  from  this  group.) 

13.  a)  Given  one  battery,  one  bell,  two  push  buttons,  and  a  quantity  of  wire, 

represent  by  a  simple  diagram  a  scheme  for  wiring  a  house  so  that  the 
bell  may  be  rung  from  either  the  front  door  or  the  back  door. 

b)  Why  is  it  advantageous  to  use  a  high  voltage  for  the  transmission  of  elec- 

tric energy  over  long  distances  ? 

c)  Why  are  alternating  currents  used  for  long  distance  electrical  transmission  ? 

14.  A  17-candle-powcr   carbon  filament  lamp  takes  0.6  ampere  at  110  volts. 

A  2G0-candle-power  gas  filled  tungsten  filament  lamp  takes  1.85  amperes 
at  110  volts.     Compare  the  efficiencies  of  the  two  lamps. 

15.  The  poles  of  a  storage  cell  having  an  electromotive  force  of  2  volts  and  an 

internal  resistance  of  0.1  ohm  are  connected  by  two  wires  in  parallel  whose 
resistances  are  12  ohms  and  4  ohms  respectively. 

a)  What  current  flows  in  each  wire  ? 

b)  What  current  flows  through  the  cell  ? 


COMPREHENSIVE  PHYSICS 


"7 


I9i6 

Comprehensive  Examination 


PHYSICS 

Friday,  June  23  9:00  a.m.-i2:oo  m. 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  part 
of  the  examination,  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  questions.  Show  clearly  the  method  by  which  you  obtain  your  answers, 
and  state  the  units  used  in  each  case. 

1.  a)  What  is  meant  by  potential  energy  ?  by  kinetic  energy  ?     Give  examples. 
h)  A  body  whose  mass  is  50  gm.  is  raised  to  a  height  of  300  cm.     What  is 

its  potential  energy  ? 

c)  If  it  is  allowed  to  fall  freely,  what  will  be  its  potential  energy  after  it  has 

fallen  through  a  distance  of  100  cm.  ?     What  is  its  kinetic  energy  at 
this  point  ?     What  is  the  sum  of  these  two  energies  ? 

d)  After  it  has  fallen  through  the  whole  distance,  300  cm.,  what  is  its  kinetic 

energy  ? 

e)  What  principle  do  the  combined  answers  to  (6),  (c),  and  {d)  illustrate  ? 

2.  Define  coefficient  of  friction;   mechanical  advantage. 

A  boat  weighing  1,800  lbs.  is  to  be  drawn  to  a  point  above  high  water  level 
along  a  beach  which  rises  3  ft.  in  10  ft.  Make  a  sketch  of  a  six-rope  block 
and  tackle  adapted  to  the  foregoing  purpose,  and  calculate  the  force 
required,  assuming  the  coefficient  of  friction  between  the  boat  and  the 
beach  to  be  0.4, 

3.  Given  a  U-tube  and  some  water:   {a)  explain  how  you  would  determine  the 

pressure  of  the  illuminating  gas  in  the  pipes  of  a  house;  {b)  explain  how 
the  result  may  be  reduced  to  pounds  per  square  inch.  (One  cubic  foot 
of  water  weighs  62 .4  lbs.) 

4.  A  standard  life-preserver  made  of  cork,  the  specific  gravity  of  which  is  o.  14, 

measures  40  in.  X 1 2  in.  X  2  in. ;  what  extra  weight  would  the  life-preserver 
support  when  completely  immersed  in  sea-water  of  specific  gravity  1.03. 
State  the  principle  involved  in  the  solution  of  the  problem,  (i  cu.  ft.  of 
fresh  water  weighs  62.4  lbs.) 

5.  The  vibration  frequency  of  two  equal  strings  5  ft.  long  is  236  vibrations  per 

sec.  How  many  beats  per  sec.  will  be  heard  when  one  of  the  strings  has 
been  shortened  i  inch  ? 

6.  Describe  fully  a  laboratory  experiment  for  determining  the  rate  of  vibration 

of  some  body  emitting  a  sound. 

7.  What  is  the  source  of  the  heat  which  melts  the  ice  in  a  tightly  closed  refriger- 

ator ?  If  it  requires  3  lbs.  of  ice  to  cool  a  gallon  of  milk  (8 . 3  lbs.)  con- 
tained in  a  glass  jar  weighing  4  lbs.,  from  75°  F.  to  40°  F.,  what  is  the  effi- 
ciency of  the  refrigerator  ?  Assume  specific  heat  of  milk  to  be  i .  o,  specific 
heat  of  glass  to  be  o.  12,  and  the  latent  heat  of  melting  of  ice  to  be  147  in 

the  units  here  used. 

(SEE  NEXT  PAGE) 

118 


8.  A  mass  of  loo  kgm.  falls  lo  meters.     All  of  its  energy  is  employed  in  stirring 

i,ooo  gm.  of  water  contained  in  a  calorimeter  which  weighs  150  gm. 
(Specific  heat,  o.  i.)  The  temperature  is  observed  to  rise  2?3  C.  Calcu- 
late the  mechanical  equivalent  of  heat. 

9.  Define  coefficient  of  expansion.     Describe  a  laboratory  experiment  by  which 

the  coefficient  of  expansion  of  some  substance  is  determined. 

10.  What  two  classes  of  images  are  formed  by  a  concave  mirror  ?     Show  by 

diagrams  the  position  of  an  image  of  each  kind,  and  explain  the  principles 
underlying  the  construction  of  the  diagrams. 

11.  How  does  the  intensity  of  illumination  at  a  point  2  ft.  distant  from  a  32 

candle-power  lamp  compare  with  the  intensity  of  illumination  at  a  point 
3  ft.  distant  from  the  same  lamp  ?  How  far  away  from  the  above  lamp 
should  one's  book  be  placed  to  secure  an  illumination  upon  its  pages  of 
2  foot-candles  ?  (One  foot-candle  is  the  illumination  produced  by  a 
standard  candle  at  a  distance  of  one  foot.) 

12.  Glass-bottomed  boats  are  frequently  used  in  the  observation  of  the  life  in 

the  ocean.  Draw  approximately  the  path  of  a  ray  of  light,  coming  from  a 
point  some  distance  below  the  boat  bottom  and  in  the  water,  as  it  passes 
up  through  the  thick  glass  bottom  (index  of  refraction  of  glass,  1.5;  of 
water,  1.33)  (i)  when  the  direction  of  the  ray  is  perpendicular  to  the 
glass;  (2)  when  the  direction  of  the  ray  is  oblique  to  the  glass.  Give 
reasons  for  your  answers. 

13.  Describe  briefly  some  form  of  galvanometer  or  ammeter,  with  diagrams  if 

necessary,  and  explain  its  action  as  a  measuring  instrument. 
A  galvanometer  or  ammeter  having  a  resistance  of   10  ohms  is   to  be 
connected  so  as  to  take  only  one-tenth  of  the  total  current  in  the  main 
circuit.     Explain  how  this  may  be  done. 

14.  If  an  electric  flat-iron  takes  5.3  amperes  at  no  volts,  what  is  the  resistance 

of  the  heating  element  ?  How  many  watts  of  electric  power  are  required 
to  operate  the  apparatus  ?  How  many  calories  of  heat  should  it  develop 
in  10  minutes  ?  How  much  does  it  cost  per  hour  to  run  the  flat-iron  at  10 
cents  per  kilowatt-hour?     (i  watt-second  =  o .  24  calories.) 

15.  Discuss  the  principle  and  the  details  of  construction  of  a  commercial  trans- 

former. 
Why  is  it  impracticable  to  transmit  electrical  power  over  great  distances,  such 

as  from  Niagara  to  New  York  City  ?     What  changes  in  the  older  methods 

of  installation  have  led  to  considerable  extensions  in  the  practical  working 

distances  during  the  last  decade  ? 
A  commercial  transformer  was  placed  on  the  outside  of  a  building  to  change 

220  volts  to  no  volts  for  laboratory  use.     By  mistake  the  line  wires  were 

connected  to  the  secondary  terminals.     What  voltage  was  obtained  in  the 

laboratory  ? 


119 


igid 

Comprehensive  Examination 


PHYSICS 

Monday,  September  i8  2:00-5:00  p.m. 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  part 
of  the  examination,  imless  a  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  questions.  Show  clearly  the  method  by  which  you  obtain  your  answers, 
and  state  the  units  used  in  each  case. 

1.  a)  Define  kinetic  energy;  potential  energy. 

b)  A  shell  weighing  6  lbs.  fired  from  an  anti-aircraft  gun  aimed  vertically 
upward  has  a  muzzle  velocity  of  1,200  ft.  per  sec.  If  the  shell  bursts 
beside  an  aeroplane  3  sec.  after  leaving  the  gun,  how  high  is  the 
aeroplane  ? 

2.  A  boy  weighing  no  pounds  sits  in  a  hammock  whose  ropes  make  angles  of 

60°  and  30°  respectively  with  the  horizontal.  Find  the  tension  in  each 
rope. 

3.  a)  Draw  a  diagram  of  a  force  pump.     Explain  the  action  of  the  pump, 

referring  as  much  as  possible  to  your  diagram  in  giving  your  explana- 
tion. 
b)  A  1.5  horse-power  gasoUne  engine  is  used  to  drive  a  force  pump  which 
pumps  water  from  a  spring  to  a  60-gallon  tank  70  ft.  higher  than  the 
spring.  If  the  tank  is  filled  in  2  minutes,  what  is  the  efficiency  of  the 
pump  ?     (A  gallon  of  water  weighs  8 . 4  lbs.) 

4.  A  bubble  has  a  volume  of  5  c.c.  and  is  at  a  depth  of  i  meter  below  the  surface 

of  water,  the  barometer  reading  70  cm.  of  mercury.  If  the  barometric 
pressure  changes  to  73  cm.,  what  will  be  the  resulting  volume  of  the  bubble  ? 
(Specific  gravity  of  mercury  =13. 6.) 

5.  Explain  the  action  of  a  megaphone.     Give  a  physical  explanation  of  the 

reason  that  sound  can  be  transmitted  to  greater  distances  through  a 
speaking-tube  than  in  the  open.  Why  does  the  presence  of  a  large 
number  of  people  in  an  auditorium  improve  its  acoustic  properties,  that 
is,  make  it  easier  to  understand  the  speaker? 

6.  a)  The  sound  of  a  fire-alarm  is  heard  3  sec.  after  the  bell  is  struck  by  the 

hammer.     If  the  temperature  of  the  air  is  at  68°  F.,  how  far  away  is 
the  bell? 
b)  If  the  A  above  middle  C,  tuned  to  435  vibrations  per  second,  is  the  standard 
pitch  for  the  orchestra,  what  is  the  vibration  frequency  of  middle  C 
upon  the  same  scale  ? 

(SEE  NEXT  PAGE) 


7-  What  determines  the  magnitude  of  (a)  i°  C.  ?  (b)  i°  F.  ?  In  what  respects 
would  a  gas  thermometer  be  (a)  superior  and  (b)  disadvantageous  as  com- 
pared with  a  mercury,  or  Hquid  thermometer  ?     Explain. 

8.  How  many  grams  of  steam  will  be  produced  if  i,ooo  gm.  of  lead  of  specific 

heat  0.032  at  a  temperature  of  300°  C.  are  dropped  into  100  gm.  of  water 
at  80°  C.  contained  in  a  calorimeter  of  specific  heat  o.  i  and  weight  90  gm.  ? 

9.  Why  does  hot  air  rise  ?     Why  does  frost  appear  on  the  inside  of  a  window 

pane  in  one's  living-room  before  it  appears  on  the  outside  of  the  pane? 
Why  are  hot-air  registers  placed  near  the  ceiling  and  cold-air  registers 
placed  near  the  floor  in  mechanically  ventilated  schoolrooms  ?  What  is 
the  cause  of  the  loud  hammering  heard  in  certain  steam  radiators  in  the 
early  morning  and  how  may  the  trouble  be  remedied  ?  Why  are  fur- 
nace pipes  placed  near  the  inner  walls  of  a  room  heated  by  hot  air  and  why 
are  steam  radiators  placed  near  the  outside  walls  of  a  room  heated  by 
steam  ? 

10.  Describe  a  laboratory  experiment  that  you  performed  in  which  you  used 

some  form  of  mirror,  either  plane  or  curved.  Do  this  very  completely, 
drawing  diagrams  whenever  possible.  State  not  only  what  you  did  but 
also  what  you  found  to  be  true  as  the  results  of  your  experiment. 

1 1 .  A  camera  with  a  lens  whose  principal  focal  distance  is  4  in.  permits  the  lens 

to  be  drawn  out  to  a  maximum  distance  of  5  in.  from  the  plate. 

a)  What  is  the  shortest  distance  from  the  lens  at  which  a  flat  object  may  be 

placed  in  order  to  secure  a  properly  focussed  image  ? 

b)  If  the  object  is  8  in.  high,  what  will  be  the  height  of  its  image  ? 

12.  Why  does  one's  face  appear  so  ghastly  and  one's  hps  so  purple  when  seen  by 

the  light  of  a  mercury- vapor  arc  lamp  ?  Would  the  addition  of  a  colored 
shade  to  the  lamp  improve  the  situation  ?     Explain. 

13.  Describe  an  experiment  that  you  performed  in  the  laboratory  in  which  a 

voltmeter  or  ammeter  or  some  form  of  galvanometer  was  one  of  the  pieces 
of  apparatus  used.  Draw  diagrams  where  helpful,  and  state,  not  only  what 
you  did,  but  also  the  object  of  the  experiment. 

14.  a)  A  battery,  whose  e.m.f.  when  delivering  no  current  is  2  volts  and  whose 

internal  resistance  is  6  ohms,  sends  a  current  of  j  ampere  through  an 
external  resistance  connected  across  its  terminals.     Find  the  value  of 
the  external  resistance. 
b)  How  many  watts  are  supplied  to  the  external  resistance  ? 

15.  a)  Explain  clearly  what  is  meant  by  an  alternating  current. 

b)  What  are  the  advantages  and  disadvantages  of  an  alternating  current 
as  compared  with  a  direct  current  ? 


1917 

Comprehensive  Examination 

PHYSICS 

Friday,  June  22  2-5  p.m. 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  a  part 
of  the  examination,  imless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  numbered  questions,  distributed  as  follows :  three  from  Group  I,  two  from 
Group  n,  two  from  Group  IV,  two  from  Group  V,  and  one  of  the  remaining  questions. 

The  number  in  parenthesis  before  each  question  indicates  the  number  of  credits 
assigned  to  it. 

Show  clearly  the  method  by  which  you  obtained  your  answers  to  problems  and  state 
the  units  used  in  each  case. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Group  I 

1.  If  a  10-gram  body  should  start  from  rest  down  a  frictionless  plane  and  gain 

in  six  seconds  a  velocity  of  120  cm.  per  second,  what  would  be: 

a)  (2)  tlie  total  distance  covered  ? 

h)  (2)  the  distance  covered  during  the  first  second  ? 

c)  (2)  the  distance  covered  during  tlie  last  second  ? 

d)  (2)  the  acceleration  ? 

e)  (2)  the  kinetic  energy  at  the  end  of  six  seconds  ? 

2.  a)  (2)  Define  horse-power. 

b)  (6)  An  automobile  running  at  the  constant  rate  of  30  miles  per  hour 

exerts  a  force  of  200  lbs.  in  the  direction  of  motion.     What  is  the 
power  supplied  to  the  wheels  of  the  automobile  ? 

c)  (2)  If  the  efl&ciency  of  the  transmitting  mechanism  is  75  per  cent,  what 

horse-power  is  the  engine  developing  ? 

3.  a)  (7)  A  uniform  plank,  AB,  12  ft.  long  and  weighing  80  lbs.,  is  used  as  a 

"diving-board."  End  A  is  fastened  to  the  floor  of  a  float.  Four 
ft.  from  A  the  plank  rests  on  the  slightly  raised  edge  C  of  the  float, 
so  that  8  ft.  of  the  plank  projects  over  the  water.  A  boy  weighing 
100  lbs.  stands  on  end  B  and  a  second  boy  of  60  lbs.  weight,  1  ft.  from 
him.  Under  these  conditions,  how  strong  must  the  fastenings  be 
at^.? 
h)  (3)  What  is  the  direction  and  magnitude  of  the  force  exerted  at  C? 
Make  a  diagram. 

4.  a)  (7)  A  building  is  being  moved  on  rollers  on  a  level  road  by  means  of  a 

capstan  (a  form  of  the  wheel-and-axle  machine).  Two  horses,  each 
exerting  an  effective  pull  of  125  lbs.,  are  attached  to  the  capstan 
bar  (wheel)  at  a  distance  of  7  ft.  from  the  center  of  the  drum  (axle). 
This  drum,  on  which  the  ro])e  attached  to  the  house  is  wound,  is 
G  in.  in  diameter.  If  the  coefficient  of  friction  of  the  building  on  the 
rollers  is  0.3,  what  is  the  weight  of  the  building?  Neglect  other 
friction. 
b)  (3)  If  the  horses  make  5  circuits  per  minute,  what  is  the  rate  of  working 
of  the  team  ? 

(SEE  NEXT  PAGE) 


6.  a)  (7)  A  hollow  sphere  of  glass  weighs  500  gm.  in  air  and  requires  a  force  of 
1,000  gm.  to  hold  it  under  water.     If  the  density  of  the  glass  is  2.5 
gm.  per  cu.  cm.,  what  is  the  volume  of  the  space  inside  ? 
b)  (3)  Is  it  harder  to  lift  a  stone  in  air  than  when  it  is  under  water  ?     Why  ? 

Group  II 

6.  (10)  An  automobile  tire  contains  1,500  cu.  in.  of  air  at  12°  C.  and  a  pressure 

of  90  lbs.  per  sq.  in.  Driving  the  car  causes  the  air  in  the  tire  to  be 
heated  to  33°  C.  What  is  the  pressure,  assuming  the  air  in  the  tire 
to  have  now  a  volume  of  1,530  cu.  in.  ? 

7.  a)  (4)  Describe  the  processes  by  which  heat  passes  from  the  steam  in  a  steam 

radiator  to  the  objects  in  the  room. 
b)  (6)  Steam  at  100°  C.  is  passed  into  a  55-kg.  iron  radiator.     Calculate 
the  weight  of  steam  condensed  in  heating  the  radiator  from  5°  C. 
to  100°  C.    (Specific  heat  of  iron =0. 11.) 

8.  a)  (4)  Describe  a  laboratory  experiment  to  determine  the  latent  heat  of 

vaporization  of  water, 

b)  (4)  What  quantities  must  be  determined  and  how  would  you  use  these  in 

calculating  the  result  ? 

c)  (2)  Mention  two  important  sources  of  error  which  must  be  guarded 

against. 

Group  III 

9.  a)  (5)  Name  and  define  three  characteristics  by  which  different  sounds  are 

distinguished  from  each  other. 
b)   (5)  Explain  how  each  of  these  characteristics  may  be  altered  in  the  case 
of  a  vibrating  string. 

Group  IV 

10.  a)  (4)  Show  how  the  intensity  of  a  source  of  light  may  be  measured. 

b)  (1)  What  is  the  unit  of  intensity  of  light  ? 

c)  (5)  If  a  light  6  ft.   away  is  illuminating  your   book,   how  far  away 

should  a  light  16  times  as  bright  be  placed  to  produce  the  same 
illumination  ? 

11.  At  what  distance  from  a  double  convex  lens  of  focal  length  12  in.  must  an 

object  be  placed  to  cause  a  real  image: 

a)  (4)  of  twice  the  length  of  the  object  ? 

b)  (3)  of  half  the  length  of  the  object? 

c)  (3)  of  the  same  length  as  the  object  ? 

12.  a)  (3)  What  is  a  spectrum  and  how  is  it  produced  ? 

b)  (2)  What  are  the  Fraunhofer  lines  in  the  solar  spectrum  ? 

c)  (2)  What  do  these  lines  indicate  ? 

d)  (3)  Explain  the  appearance  of  each  color  in  the  American  flag  when  placed 

in  pure  blue  light;    when  placed  in  pure  red  light. 

(SEE  NEXT  PAGE) 


Group  V 

13.  a)  (2)  Describe  a  leaf  electroscope. 

b)  (3)  Describe  how  tlie  electroscope  may  be  charged  by  the  method  of 

induction. 

c)  (3)  Explain  tlie  various  steps  of  the  process. 

d)  (2)  Explain  how  tlie  electroscope  is  used  to  tell  that  a  body  is  positively         ^ 

charged.  ' 

14.  A  40-watt  incandescent  lamp  is  connected  to  a  100-volt  circuit: 
c)  (3)  What  current  passes  through  the  lamp  ? 

b)  (2)  If  three  such  lamps  are  connected  in  parallel  in  the  above  circuit,  what 

current  passes  through  each  lamp  ? 

c)  (2)  If  the  three  lamps  are  connected  in  series,  what  current  passes  through 

each  lamp  ? 

d)  (3)  If  the  three  lamps  are  connected  in  parallel  and  used  10  hours  each 

day  for  4  weeks,  and  the  cost  is  8  cents  per  kilowatt-hour,  what  will 
be  the  total  cost  ? 

15.  a)  (1)  Whose  name  is  associated  with  the  discovery  of  induced  currents? 

b)  (2)  What  is  Lenz's  Law  for  the  direction  of  induced  currents  ? 

c)  (2)  Name  two  machines  or  pieces  of  apparatus  that  depend  upon  induc- 

tion for  their  usefulness. 

d)  (!)  In  what  other  way  are  currents  of  electricity  commonly  produced  ? 

e)  (1)  Which  was  discovered  first  ? 

/)    (1)  Which  is  the  more  important  today  ? 

g)   (2)  Give  some  reasons  for  your  last  answer.  ;|| 


1-4 


1917 
Comprehensive  Examination 


PHYSICS 

Monday,  September  17  2-5  p.m. 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  a  part 
of  the  examination,  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory 
examination. 

Answer  ten  numbered  questions,  distributed  as  follows:  three  from  Group  I,  two  from 
Group  II,  two  from  Group  IV,  two  from  Group  V,  and  one  of  the  remaining  questions. 

The  nimiber  in  parenthesis  before  each  question  indicates  the  number  of  credits 
assigned  to  it. 

Show  clearly  the  method  by  which  you  obtained  your  answers  to  problems  and  state 
the  units  used  in  each  case. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Table  of  Constants 

Acceleration  of  gravity =980  cm.  per  sec.  per  sec. 
1  horse-power  =  746  watts. 

Group  I 

1.  a)  (5)  A  100-lb.  child  in  a  swing  is  pushed  9  ft.  away  from  the  vertical,  the 

distance  from  the  top  of  the  swing  to  the  center  of  gravity  of  the 
child  being  15  ft.     What  horizontal  force  is  necessary  to  hold  him 
in  his  new  position  ? 
b)   (5)  What  is  the  strain  on  each  of  the  swing  ropes  ? 

2.  a)  (6)  A  uniform  plank  20  ft.  long  weighing  50  lbs.  rests  on  a  support  6  ft. 

from  one  end.     The  plank  is  held  in  a  horizontal  position  by  a  verti- 
cal rope  attached  to  the  other  end  of  the  plank.     What  is  the  force 
on  the  support  and  the  tension  in  the  rope  ? 
b)   (4)  How  far  from  the  support  can  a  boy  of  80  lbs.  walk  before  the  plank 
tips  ?     ]\Iake  a  diagram. 

3.  A  box  weighing  200  lbs.  is  pushed  up  a  plank  10  ft.  long  into  a  wagon  4  ft. 

high.     Disregarding  friction: 

a)  (3)  What  force  is  necessary  to  keep  the  box  from  sliding  down  the  plank  ? 

b)  (2)  What  work  is  done  in  pushing  the  box  from  the  ground  into  the  wagon  ? 

If  a  force  of  30  lbs.  is  required  to  overcome  friction: 

c)  (3)  What  is  now  the  total  work  done  ? 

d)  (2)  What  is  tlie  efficiency  in  this  case  ? 

4.  a)  (3)  State  the  principle  of  the  conservation  of  energy. 

b)  (7)  A  142-gm.  baselmll  is  dropped  from  the  Washington  monument,  a 
distance  of  160  m.  If  tliis  ball  is  caught  and  is  stopped  within  a 
distance  of  80  cm.,  what  is  the  average  force  it  will  exert  upon  the 
catcher's  hand  ?     Neglect  the  resistance  of  the  air. 

(SEE  NEXT  PAGE) 

125 


5.  a)  (2)  Define  density ;  specific  gravity. 

b)  (8)  When  a  meter  stick  is  made  to  float  upright  in  pure  water,  18.5  cm. 
of  the  stick  projects  above  the  water  and  when  similarly  floated 
in  a  second  liquid,  24  cm.  of  the  stick  projects  above.  What  are 
the  specific  gravities  of  the  second  liquid  and  the  meter  stick  ? 

Group  II 

6.  a)  (6)  A  50-ft.  steel  tape  is  correct  at  20°  C.     How  long  would  it  be  at  a 

temperature  of  — 10°  C.  ?     (Coefficient  of  linear  expansion  of  steel 
=0.000012.) 
b)   (4)  Describe  two  instances  where  the  change  of  size  of  a  solid  with  change 
of  temperature  is  of  practical  use;    and  two  instances  where  the 
change  of  size  is  not  desired  but  has  to  be  allowed  for. 

7.  a)  (4)  Why  does  a  person  feel  more  comfortable  on  a  hot  dry  day  than  on 

a  humid  day  of  the  same  temperature  ? 
b)   (6)  100  gm.  of  a  liquid  whose  specific  heat  is  0.6  and  temperature  80°  C. 
are  mbced  with  300  gm.  of  water  at  15°  C.     What  will  be  the 
temperature  of  the  mixture  ?    Assume  the  interchange  of  heat  to 
be  confined  to  the  two  liquids. 

8.  a)  (3)  What  is  the  essential  feature  in  the  construction  of  a  "  fireless  cooker  "  ? 

b)  (2)  Is  the  cooking  done  entirely  without  a  source  of  heat  ? 

c)  (2)  Explain  wherein  its  use  is  economical  of  heat. 

d)  (3)  What  is  meant  by  conduction  of  heat;  by  convection;  by  radiation? 

Group  III 

9.  a)  (3)  What  do  the  terms  "frequency"  and  "wave-length"  mean,  as  used 

in  the  study  of  sound  ? 

b)  (4)  If  low  C  has  a  frequency  of  128,  what  is  the  frequency  and  wave- 

length at  0°  C.  of  the  note  one  octave  higher  ? 

c)  (3)  State  and  explain  the  effect  on  the  pitch  of  increasing  the  speed  of  a 

phonograph. 

Group  IV 

10.  a)  (2)  State  the  law  of  reflection  of  light,  making  use  of  a  diagram. 

b)  (5)  A  plane  or  convex  mirror  is  often  placed  on  an  automobile  to  allow 

the  driver  to  see  in  it  the  reflection  of  what  is  in  the  rear.     What  are 
the  advantages  of  the  convex  mirror;  of  the  plane  ? 

c)  (3)  Why  is  not  a  concave  mirror,  which  may  form  a  magnified  image, 

better  than  either  of  the  others  for  the  purpose  ? 

11.  a)  (4)  Describe  in  detail  a  laboratory  method  of  determining  the  index  of 

refraction  of  glass  or  of  water. 

b)  (4)  What  measurements  must  be  made  and  how  is  the  index  computed 

from  them  ? 

c)  (2)  What  is  the  velocity  of  light  through  water  ?     (Index  of  refraction  of 

water  =1.33.) 


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126 


12.  a)  (2)  Wherein  does  blue  light  differ  from  red  light  ? 

b)  (2)  If  an  object  colored  a  pure  red  (such  as  a  red  rose)  is  illuminated  by- 

pure  blue  light  only,  what  is  the  effect  on  its  appearance  ? 

c)  (2)  Explain  the  cause  of  this  effect. 

d)  (2)  What  are  infra-red  rays;  ultra-violet  rays? 

e)  (2)  How  may  each  be  detected  ? 

Group  V 

13.  a)  (3)  Make  a  sketch  of  an  electromagnet,  showing  clearly  the  direction  of 

the  current  through  the  wire,  and  the  resulting  polarity  of  each 
end  of  the  magnet. 

b)  (2)  Mention  two  important  uses  of  the  electromagnet. 

c)  (2)  What  are  its  advantages  over  a  permanent  steel  magnet  ? 

d)  (3)  Suppose  you  were  presented  with  two  steel  bars  exactly  alike  except 

that  one  was  magnetized.     How  could  you  decide  which  was  the 
magnet  ? 

14.  a)   (4)  A  certain  incandescent  lamp  of  constant  resistance  takes  50  watts  from 

a  100-volt  circuit.     How  much  power  will  it  take  from  a  200-volt 
circuit  ? 

b)  (4)  How  much  power  will  two  such  lamps  in  series  take  from  the  200-volt 

line? 

c)  (2)  What  is  the  current  flowing  in  each  of  the  above  three  cases  ? 

15.  a)  (6)  A  J  horse-power  motor,  a  750-watt  electric  sto\-e,  and  an  electric  flat- 

iron  using  5  amperes  are  connected  in  parallel  on  a  110-volt  circuit. 
What  is  tlie  total  current  ? 
b)  (4)  What  would  be  the  cost  of  using  this  current  for  half  an  hour  at  3 
cents  per  kilowatt-hour? 


i-27 


1918 
Comprehensive  Examination 


PHYSICS 

Friday,  June  21  2-5  p.m. 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  a  part 
of  the  examination  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory  exami- 
nation. 

Answer  ten  ntmibered  questions,  distributed  as  follows:  three  from  Group  I,  two  from 
Group  II,  two  from  Group  IV,  two  from  Group  V,  and  one  of  the  remaining  questions. 

The  niunber  in  parenthesis  before  each  question  indicates  the  nimiber  of  credits 
assigned  to  it. 

Show  clearly  the  method  by  which  you  obtained  your  answers  to  problems  and  state 
the  units  used  in  each  case. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Group  I 

1.  A  wooden  cube  5  cm.  on  an  edge  weighs  100  g. 

a)  (3)  What  is  the  density  of  the  cube  ? 

b)  (3)  What  force  would  be  required  to  hold  the  cube  submerged  in  a  liquid 

having  a  density  of  1 .5  g.  per  cu.  cm.  ? 

c)  (4)  How  much  of  its  volume  would  protrude  above  the  surface  if  the 

cube  were  floated  in  a  liquid  having  a  density  of  1 .2  g.  per  cu.  cm.  ? 

2.  a)  (3)  Define  work;    mechanical  advantage  of  a  machine;   efl&ciency  of  a 

machine. 
b)  (7)  Two  men  raise  a  weight  by  means  of  a  jackscrew.  They  push  with  a 
force  of  100  lbs.  each,  at  opposite  ends  of  a  bar  5  ft.  long  that  passes 
through  a  hole  at  the  top  of  the  screw.  If  the  pitch  of  the  screw  is 
I  inch  and  the  efi&ciency  of  the  machine  is  30  per  cent,  how  great  is 
the  weight  ? 

3.  An  engine  operates  a  pump  which  raises  water  to  a  height  of  50  ft.  at  the  rate 

of  1,000  gal.  per  min.     (One  gallon  of  water  weighs  8.4  lbs.) 

a)  (3)  How  much  work  is  done  upon  the  water  per  second  ? 

b)  (7)  If  the  efficiency  of  the  pump  is  90  per  cent,  how  many  horse-poM^er 

is  the  engine  developing  ? 

4.  A  constant  force  acting  on  a  mass  of  40  grams  for  5  seconds  changes  its 

velocity  from  60  cm.  per  second  to  100  cm.  per  second.     What  is: 

a)  (2)  the  acceleration  ? 

b)  (2)  the  magnitude  of  the  force? 

c)  (2)  the  total  distance  covered  in  the  five  seconds  ? 

d)  (2)  the  final  momentum  ? 

e)  (2)  the  kinetic  energy  at  the  end  of  the  first  two  seconds  ? 


(SEE  NEXT  PAGE) 

I2S  . 


5.  a)  (8)  A  tank  having  a  volume  of  12  cu.  ft.  contains  air  under  a  pressure  of 

30  lbs.  per  sq.  in.    On  connecting  the  tank  to  an  exhausted  recepticle 
the  air  pressure  is  reduced  to  10  lbs.  per  sq.  in.     Find  the  volume  of 
the  recepticle. 
h)  (2)  Describe  two  phenom.ena  that  are  caused  by  surface  tension. 

Group  II 

6.  a)  (2)  Define  coefficient  of  linear  expansion. 

b)  (8)  Describe  an  experimental  method  of  measuring  the  coefficient  of 

linear  expansion  of  a  solid,  describing  the  apparatus  used,  the 
measurements  made,  and  the  way  in  which  these  measurements  are 
used  to  compute  the  coefficient. 

7.  a)  (6)  A  balloon  is  filled  on  a  cool  night  with  20,000  cu.  ft.  of  gas  at  a  tempera- 

ture of  7°  C.  under  a  pressure  of  15  lbs.  per  sq.  in.     In  the  sunshine 
of  the  day  the  gas  becomes  warmed.     At  what  temperature  will 
the  pressure  reach  16  lbs.  per  sq.  in.  ?     Assume  that  the  gas  bag 
does  not  stretch  and  that  no  gas  escapes. 
h)  (2)  Express  9°  C.  on  the  Fahrenheit  scale. 

c)  (2)  Compare  the  advantages  of  mercury  and  of  air  as  thermometric 

substances. 

8.  (j)  (2)  Name  and  define  a  unit  quantity  of  heat. 

b)  (8)  A  copper  calorimeter  of  mass  210  g.  contains  85  g.  of  water  and  100  g. 
of  lead  shot  at  15°  C.  How  much  boiling  water  must  be  added  to 
raise  the  temperature  of  the  calorimeter  and  contents  to  25°  C.  ? 
(Sp.  ht.  of  copper  =0.095;   of  lead  =  0.032.) 

Group  III 

9.  a)  (2)  What  conditions  are  necessary  for  the  formation  of  an  echo  ? 

b)  (2)  What  is  the  physical  difference  between  a  noise  and  a  musical  sound  ? 

c)  (2)  Why  is  thunder  usually  heard  some  time  after  a  lightning  flash  is  seen  ? 

d)  (2)  Upon  what  does  the  loudness  of  sound  depend? 

e)  (2)  Upon  what  does  the  pitch  of  a  sound  depend  ? 

Group  IV 
10.  a)  (3)  A  more  sharply  defined  shadow  is  cast  by  an  opaque  body  when  the 

source  of  Hght  is  an  arc  lamp  than  when  it  is  a  gas  jet.     Explain 

by  the  aid  of  diagrams. 
h)  (3)  What  should  be  the  brightness  of  a  single  light  in  the  ceiling  10  ft. 

from  a  book  to  give  the  same  illumination  as  two  candles  placed 

one  foot  from  the  book  ? 
c)  (4)  Ex-plain  what  is  meant  by  saying  that  the  index  of  refraction  of 

water  is  |.     Make  a  careful,  fully  labeled  diagram  showing  the 

passage  of  a  ray  of  light  obliquely  from  air  into  water. 

{SEE  NEXT  PAGE) 

IZC) 


11.  a)  (2)  Define  principal  focus;  conjugate  foci. 

A  moving-picture  machine  is  to  be  designed  to  project  the  picture  on  the 
film  upon  a  screen  60  ft.  from  the  film.  If  the  image  on  the  screen  is  to  be  119 
times  the  linear  dimensions  of  the  picture  on  the  film : 

b)  (2)  How  far  from  the  film  must  the  projection  lens  be  placed  ? 

c)  (4)  What  must  be  the  focal  length  of  the  lens  ? 

d)  (2)  How  many  times  as  intense  will  be  the  light  passing  through  the  film 

as  that  falling  on  the  screen  ? 

12.  a)  (4)  Make  a  diagram  to  show  the  dispersion  of  a  narrow  beam  of  sunlight 

by  a  triangular  glass  prism. 

b)  (4)  What  is  the  explanation  of  refraction  ?  of  dispersion  ? 

c)  (2)  Explain  carefully  why  the  same  blue  cloth  may  seem  to  be  of  a  different 

color  when  viewed  by  gaslight  and  by  sunlight. 

Group  V 

13.  a)  (2)  What  type  of  cell  is  best  adapted  to  the  ringing  of  electric  bells? 

Why? 

b)  (2)  What  is  meant  by  the  term  local  action  as  applied  to  voltaic  cells  ? 

c)  (2)  How  may  local  action  be  reduced  ? 

d)  (2)  What  is  meant  by  polarization  of  cells  ? 

e)  (2)  How  may  polarization  be  reduced? 

14.  Two  resistance  coils  of  10  and  30  ohms  joined  in  parallel  are  connected  in 

series  with  a  key,  an  ammeter  of  negligible  resistance,  and  a  battery  whose 
electromotive  force  is  21  volts  and  whose  internal  resistance  is  3  ohms.  A 
voltmeter  of  high  resistance  is  connected  in  parallel  with  the  battery. 

a)  (2)  Draw  a  diagram  of  the  connections. 

b)  (2)  \\1iat  will  be  the  ammeter  and  voltmeter  readings  when  the  key  is 

open? 

c)  (6)  What  will  the  readings  be  when  the  key  is  closed  ? 

15.  (10)  Describe  the  construction  and  operation  of  two  of  the  following :  electric 

bell;   telegraph  key  and  sounder;   telephone  receiver.     IDustrate  by 
carefully  drawn  diagrams. 


^o 


1918 

Comprehensive  Examination 


PHYSICS 

Monday,  September  16  2-5  p.m. 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  a  part 
of  the  examination  unless  the  laboratory  notebook  is  to  be  presented  at  a  laboratory  exami- 
nation. 

Answer  ten  numbered  questions,  distributed  as  follows:  three  from  Group  I,  two  from 
Group  n,  two  from  Group  IV,  two  from  Group  V,  and  one  of  the  remaining  questions. 

The  number  in  parenthesis  before  each  question  indicates  the  number  of  credits 
assigned  to  it. 

Show  clearly  the  method  by  which  you  obtained  your  answers  to  problems  and  state 
the  units  used  in  each  case. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Group  I 

1.  A  hollow  box,  10X20X40  cm.  on  outside  measurements,  weighs  1,000  g. 

when  empty.     How  many  cu.  cm.  of  stone  of  specific  gravity  2.5  must  be 
put  into  the  box: 

a)  (4)  to  sink  it  in  water  ? 

b)  (4)  to  cause  it  to  float  with  -i\  of  its  volume  above  water  ? 

c)  (2)  A  vessel  is  moving  at  the  rate  of  8  miles  per  hour.     A  boy  drops  a 

ball  from  the  mast  to  the  deck.     The  ball  takes  2  seconds  to  fall. 
At  what  point  will  it  strike  the  deck  ? 

2.  a)  (3)  How  heavy  a  car  can  be  drawn  at  a  uniform  rate  along  a  horizontal 

track  by  a  horse  pulling  parallel  to  the  track  with  a  force  of  100  lbs. 
if  the  coefficient  of  friction  between  the  car  and  the  track  is  0.08? 

b)  (5)  If  the  car  moves  at  the  rate  of  4  miles  per  hour,  at  what  rate  does  the 

horse  work  ? 

c)  (2)  Why  is  the  outer  rail  on  a  curved  railway  track  placed  higher  than 

the  inner  rail  ? 

3.  A  uniform  horizontal  bar  8  ft.  long  and  weighing  9  lbs.  is  hinged  at  one  end 

and  carries  a  weight  of  6  lbs.  at  the  other  end.     The  bar  is  supported 
by  a  vertical  rope  attached  3  ft.  from  the  hinge.     Draw  a  diagram. 

a)  (4)  What  is  the  tension  in  the  rope  ? 

b)  (1)  What  is  the  direction  of  the  force  acting  on  the  bar  at  the  hinge  ? 

c)  (3)  What  is  the  magnitude  of  the  force  acting  on  the  bar  at  the  hinge  ? 

d)  (2)  What  is  the  mechanical  advantage  of  the  rope  in  raising  the  6-lb. 

weight  ? 

4.  A  200-gram  stone  thrown  along  the  surface  of  a  horizontal  sheet  of  ice  has 

its  speed  reduced  from  12  m.  per  sec.  to  4  m.  per  sec.  in  10  sec. 

a)  (2)  What  is  the  acceleration  (supposed  to  be  uniform)  ? 

b)  (2)  WTiat  is  the  retarding  force  ? 

c)  (4)  How  much  kinetic  energy  does  the  stone  lose  in  these  10  sec.  ? 

d)  (2)  How  much  work  is  done  against  friction  in  that  time  ? 

(SEE  NEXT  PAGE) 


5.  a)  (2)  Draw  a  diagram  showing  the  essential  parts  of  a  suction  pump. 

b)  (4)  Explain  the  action  of  the  pump,  referring  to  the  diagram. 

c)  (2)  What  is  the  approximate  height  to  which  water  can  be  raised  by 

suction  ? 

d)  (2)  What  imposes  a  limit  to  the  height  to  which  water  can  be  raised  by 

suction  ? 

Group  II 

6.  a)  (2)  Describe  two  instances  in  which  allowance  has  to  be  made  for  the 

change  of  size  of  bodies  with  change  of  temperature. 

b)  (2)  Give  an  example  of  a  practical  use  made  of  the  fact  that  different 

solids  do  not  all  expand  at  the  same  rate. 

c)  (2)  What  use  is  made  of  the  fact  that  platinum  and  glass  have  practically 

the  same  rate  of  expansion  ? 

d)  (4)  An  iron  steampipe  is  400  cm.  long.    Through  how  many  degrees 

Centigrade  must  it  be  heated  to  increase  its  length  0.4  cm.  ?  (Co- 
efficient of  linear  expansion  of  iron  =  0.000011  per  degree  C.) 

7.  a)  (2)  Explain    clearly    the    distinction    between    quantity   of   heat   and 

temperature. 

b)  (3)  State  a  method  of  measuring  temperature  and  state  the  facts  on 

which  it  is  based. 

c)  (3)  State  a  method  of  measuring  quantities  of  heat  and  state  the  prin- 

ciple involved. 

d)  (2)  The  normal  temperature  of  the  human  body  is  98|°  F.     Express  this 

temperature  on  the  Centigrade  scale. 

8.  a)  (3)  What  transformations  of  energy  take  place  in  generating  electricity 

from  coal  by  a  steam  engine  ? 

b)  (2)  State  two  ways  in  which  energy  is  "lost"  during  these  transforma- 

tions, and  tell  how  such  losses  may  be  reduced. 

c)  (5)  The  heat  value  of  a  certain  kind  of  coal  is  8,000  calories  per  gram. 

How  many  grams  of  coal  must  be  burned  under  a  boiler  of  60  per 
cent  efficiency  to  heat  100,000  g.  of  water  from  15°  C.  to  the 
boiling-point  and  to  change  it  to  steam  under  normal  pressure  ? 

Group  III 

9.  a)  (2)  What  is  the  cause  of  beats  in  sound  ? 

b)  (2)  How  is  it  possible  by  means  of  beats  to  tune  in  unison  two  strings  that 

differ  slightly  in  pitch? 

c)  (1)  What  is  the  value  of  the  sounding  board  on  a  musical  instrument  ? 

d)  (1)  What  is  a  fundamental  tone  ? 

e)  (1)  What  is  a  node? 

/)  (3)  What  is  the  relative  loudness  of  the  sound  of  the  discharge  of  a  gun 
as  heard  by  A  a  mile  from  the  gun  and  as  heard  by  B  a  quarter 
of  a  mile  from  the  gun  ? 

(SEE  NEXT  PAGE) 

132 


4. 


Group  IV 

10.  a)  (2)  State  the  modern  theory  of  light. 

b)  (2)  How  is  the  spectroscope  used  to  help  us  in  determining  what  chemical 

elements  are  present  in  a  body  ? 

c)  (2)  What  is  the  physical  difference  between  blue  light  and  red  light  ? 

d)  (4)  A  candle  and  an  electric  light  64  times  as  bright  as  the  candle  are  9  ft. 

apart  in  a  (Bunscn)  photometer.     Where  between  them  is  the  pho- 
tometer screen  when  its  opposite  sides  are  equally  illuminated  ? 

11.  a)  (4)  A  lens  is  used  to  produce  a  picture  8  ft.  high  of  a  three-inch  object. 

What  focal  length  does  the  lens  have  if  the  screen  on  which  the  pic- 
ture is  formed  is  24  ft.  from  the  lens  ? 

b)  (1)  What  kind  of  an  image  is  formed  in  this  case  ? 

c)  (1)  Is  the  image  erect  or  inverted  ? 

d)  (4)  Make  good-sized  sketches  of  the  essential  optical  parts  of  the  eye  and 

of  the  photographic  camera.     Show  their  optical  similarity  by  indi- 
cating the  corresponding  parts  and  stating  the  function  of  each  part. 

12.  a)  (2)  Define  the  term  complementary  colors. 

b)  (3)  Describe  an  experiment  which  may  be  performed  to  demonstrate  such 

colors. 

c)  (3)  When  pulverized  blue  and  yellow  crayons  are  mixed  the  resulting  color 

is  green.     Explain. 

d)  (2)  Give  the  names  of  two  men  who  have  contributed  to  our  knowledge  of 

light.     What  were  their  contributions  ? 

Group  V 

13.  (10)  State  the  function  of  each  of  the  following  electrical  devices:    fuse, 

storage  battery,  transformer,  dynamo,  motor,  rheostat,  Wheatstone 
bridge,  induction  coil,  electroscope,  galvanometer. 

14.  A  2-ohm  coil  and  a  3-ohm  coil  joined  in  parallel  are  connected  in  series  with  a 

5.5-ohm  coil  and  a  battery  having  an  electromotive  force  of  15  volts  and 
an  internal  resistance  of  0.8  ohm. 

a)  (3)  What  is  the  current  in  amperes  flowing  through  the  5.5-ohm  coil? 

b)  (3)  What  fraction  of  this  current  flows  through  the  2-ohm  coil  ? 

r)  (2)  At  what  rate  in  watts  does  the  battery  generate  electrical  energy  ? 
d)  (2)  How  much  power  is  being  absorbed  by  the  3-ohm  coil  ? 

15.  a)  (3)  How  long  would  it  take  a  current  of  3  amperes  to  deposit  16.5  g. 

of  copper  by  electrolysis  ?    (Electrochemical  equivalent  of  copper  = 
0.00033  g.  per  coulomb  [ampere-sec.].) 

b)  (4)  To  what  phenomena  do  the  terms  "electrostatic  induction"  and 

"electromagnetic  induction"  refer?    Describe  an  example  of  each. 

c)  (3)  A  compass  needle  is  placed  above  a  wire  running  north  and  south. 

What  may  be  inferred  if  the  needle  points  north  ?  northwest  ? 
northeast?  if  it  vibrates? 

'^35 


Page  1 

1919 

Comprehensive  Examination 
PHYSICS 

Friday,  June  20  2-5  p.m. 

Answer  ten  numbered  questions,  distributed  as  follows:  three  from  Group  I,  two  from 
Group  n,  two  from  Group  IV,  two  from  Group  V,  and  any  one  of  the  remaining  questions. 

Show  clearly  the  method  by  which  you  obtained  your  answers  to  problems  and  state 
the  imits  used  in  each  case. 

Attach  to  the  answer  in  each  case  the  number  and  letter  used  in  the  printed  paper. 

Group  I 

1.  A  submarine  weighs  1800  tons  when  its  submerging  tanks  are  empty,  and  in 

that  condition  10  per  cent  by  volume  of  the  submarine  is  above  water. 

a)  What  weight  of  water  must  be  let  into  the  tanks  just  to  submerge  the 

boat? 

b)  If  the  specific  gravity  of  sea- water  is  1.03,  what  volume  of  water  is 

required  to  submerge  the  boat  ? 

c)  What  is  the  total  force,  due  to  water  alone,  against  the  hatch,  3  by  4  ft. 

in  size,  at  a  depth  of  100  ft.  in  the  ocean  ? 

2.  A  uniform  pole,  AB,  10  ft.  long  and  weighing  16  lbs.,  has  a  10-lb.  weight 

attached  4  ft.  from  the  end  A.  The  pole  is  carried  by  two  men,  one  at  the 
end  B  and  the  other  2  ft.  from  the  end  A. 

a)  How  much  does  each  man  carry  when  the  pole  is  held  in  a  horizontal 

position  ? 

b)  What  difference  would  it  make  if  the  end  B  were  more  elevated  than  the 

end  A  ? 

3.  A  bicycle  tire  contains  120  cu.  in.  of  air  at  a  pressure  of  20  lbs.  per  square 

inch.  How  many  strokes  must  be  made  on  a  pump  whose  cylinder  has  a 
volume  of  5  cu.  in.  to  increase  the  pressure  in  the  tire  to  30  lbs.  per  square 
inch  ?  Consider  the  atmosphere  as  having  a  pressure  of  15  lbs.  per  square 
inch  and  the  volume  of  the  tire  and  the  temperature  of  the  contained  air 
to  remain  constant. 

4.  a)  How  long  must  a  force  of  2  lbs.  act  upon  a  mass  of  10  lbs.  to  give  it  a 

velocity  of  20  ft.  per  second  ? 
b)  How  much  work  will  the  force  do  in  the  time  involved  ? 

5.  What  is  the  force  of  the  backward  thrust  of  the  propeller  of  an  airplane 

driven  by  an  engine  developing  150  horse-power,  when  the  airplane  is 
traveling  120  miles  per  hour? 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 
^34 


Page  2 

Group  II 

6.  a)  Explain  why  pans  of  water  in  a  greenhouse  may  prevent  the  freezing  of 

plants. 

b)  Discuss  the  effect  of  sprinkling  the  streets  on  a  hot  day  with  water  having 
J2  the  same  temperature  as  the  air. 

c)  Why  are  very  hot  days  more  unpleasant  in  moist  than  in  dry  climates  ? 

7.  a)  Draw  a  diagram  and  explain  the  use  of  apparatus  such  as  might  be  used 

in  a  laboratory  for  obtaining  distilled  water. 
b)  In  an  apparatus  for  obtaining  distilled  water  800  grams  of  water  are  con- 
tained in  a  copper  vessel  weighing  300  grams.  Both  are  at  a  tempera- 
ture of  20°  C.  How  many  calories  of  heat  will  be  used  in  heating  the 
containing  vessel  and  in  distilling  the  water?  (The  specific  heat  of 
copper  =  0.093.) 

8.  a)  Explain  what  is  meant  by  the  mechanical  equivalent  of  heat. 

b)  In  an  apparatus  for  determining  the  mechanical  equivalent  of  heat  the 
work  done  in  producing  the  heat  was  equivalent  to  the  work  done  by  a 
200-gram  weight  falling  a  distance  of  78,570  centimeters.  If  this  heat 
raised  the  temperature  of  28  grams  of  water,  and  of  a  brass  receptacle 
weighing  190  grams  which  held  the  water,  from  17°  C.  to  25°  C,  cal- 
culate the  value  of  the  mechanical  equivalent  of  heat.  (The  specific 
heat  of  brass =0.095.) 

^  Group  III 

9.  a)  What  characteristic  of  a  note  sounded  by  a  violin  distinguishes  it  from 

the  same  note  sounded  by  a  cornet  ? 
b)  What  is  the  vibration  rate  of  an  organ  pipe  which  sends  out  sound  waves 
4.4  ft.  long  when  the  temperature  is  20°  C.  ? 

Group  IV 

10.  It  is  desired  to  project  a  real  magnified  image  on  a  screen.    Would  it  be  pos- 

sible to  do  this  by  means  of: 

a)  A  plane  mirror  ? 

b)  A  concave  mirror  ? 

c)  A  convex  mirror  ? 

Give  reasons  for  your  answers. 

11.  Given  two  converging  lenses,  one  of  1-inch  focus,  the  other  of  8-inch  focus. 

With  the  aid  of  diagrams  indicating  the  manner  in  which  the  images  are 

formed  show: 
^  a)  How  the  lenses  should  be  used  for  a  microscope. 

V  b)  How  the  lenses  should  be  used  for  a  telescope. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  3) 

135 


Pages 

12.  a)  In  making  a  photographic  print  by  an  electric  Ught  how  will  the  illumina- 

tion at  a  distance  of  5  ft.  compare  with  that  from  the  same  light  at  a 
distance  of  15  ft.  ? 

b)  If  an  exposure  of  10  seconds  is  correct  at  a  distance  of  5  ft.  what  should  be 

the  time  of  exposure  at  a  distance  of  15  ft.  ? 

c)  What  is  the  physical  difference  between  "red  light"  and  "blue  light"  ? 

Group  V 

13.  Describe  in  detail  a  method  for  determining  the  resistance  of  a  piece  of  wire, 

representing  the  scheme  of  connections  by  a  diagram. 

14.  In  an  apartment  supplied  with  direct  current  at  110  volts  there  are  two 

40-watt  lamps  and  a  heating  unit  connected  in  parallel.  In  one  week  the 
lamps  are  burned  20  hours  each  and  the  heater  is  used  25  hours.  The 
total  use  of  energy  is  7,100  watt  hours. 

a)  How  many  watts  are  used  by  the  heating  unit  ? 

b)  How  much  current  passes  through  the  heating  unit  ? 

c)  What  is  the  resistance  of  the  heating  unit  ? 

d)  What  current  flows  when  both  lamps  and  the  heating  unit  are  in  use  ? 

15.  A  direct-current  dynamo  furnishes  a  current  of  50  amperes  at  500  volts  to  a 

line  having  a  resistance  of  2  ohms. 

a)  How  much  power  is  generated  by  the  dynamo  ? 

b)  How  much  power  is  deUvered  at  the  other  end  of  the  line  ? 


136 


Page  1 

1919 
PHYSICS 

Monday,  September  15  2-5  p.m. 

Answer  ten  numbered  questions,  distributed  as  follows:  three  from  Group  I,  two  from 
Group  II,  two  from  Group  IV,  two  from  Group  V,  and  any  one  of  the  remaining  questions. 

Show  clearly  the  method  by  which  you  obtained  your  answers  to  problems  and  state 
the  units  used  in  each  case. 

Attach  to  the  answer,  in  each  case,  the  number  and  letter  used  in  the  printed  paper. 

Group  I 

1.  A  stone  of  specific  gravity  2.5,  weighing  300  lbs.  in  air,  rests  on  the  bottom 

of  a  pond.     What  work  will  be  done  in  raising  the  stone  10  ft.  through  the 
water  ? 

2.  A  tapering  telephone  pole  24  ft.  long  is  supported  at  each  end  in  a  horizontal 

position.     The  pressure  on  one  support  is  200  lbs.,  and  on  the  other  sup- 
port 120  lbs. 

a)  Locate  the  center  of  gravity  of  the  pole. 

b)  If  it  were  supported  at  its  center  of  length  only,  what  would  be  the  least 

force  that  might  be  applied  to  the  pole  that  would  keep  the  pole  hori- 
zontal ? 

3.  An  automobile  accelerates  from  rest  to  45  miles  an  hour  in  15  seconds. 

a)  If  this  acceleration  is  uniform  find  its  value  in  feet  per  second  per  second. 

b)  What  distance  did  the  car  go  in  the  first  15  seconds  ? 

4.  What  horse-power  must  be  used  to  pull  a  body  weighing  5  tons  along  a  hori- 

zontal surface  at  the  rate  of  6  miles  per  hour,  the  coefficient  of  friction 
being  0.2? 

5.  Water  is  pumped  into  the  bottom  of  an  air-tight  tank  having  a  capacity  of 

1000  gals.,  compressing  the  air  above  it  from  a  pressure  of  15  lbs.  per 
square  inch  to  a  pressure  of  50  lbs.  per  square  inch. 

a)  How  much  water  is  pumped  into  the  tank  ? 

b)  If  200  gals,  of  water  are  now  drawn  off,  what  will  be  the  air  pressure  in  the 

tank? 

Group  II 

6.  a)  Explain  under  what  conditions  frost  will  form  on  the  inside  surface  of  a 

window  of  a  house  and  not  on  the  outside  surface. 

b)  Explain  the  cooling  of  a  liquid  by  evaporation. 

c)  The  volume  of  a  mass  of  gas  is  200  cu.  cm.  at  27°  C.    At  what  tempera- 

ture will  its  volume  be  250  cu.  cm.,  if  the  pressure  is  maintained  con- 
stant? 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

7.  A  piece  of  glass  (specific  heat =0. 19)  weighing  3  kg.  and  at  a  temperature  of 

—  30°  C.  is  placed  in  water  at  0°  C.  Neglecting  the  heat  effects  upon  the 
containing  vessel  find  how  much  water  will  be  converted  into  ice  at  0°  C. 

8.  Two  kilograms  of  shot  having  specific  heat  of  0.031  are  dropped  70  meters. 

The  temperature  of  the  shot  is  found  to  have  risen  5.3°  C.  On  the 
supposition  that  all  the  heat  generated  was  retained  by  the  shot,  calculate 
the  mechanical  equivalent  of  heat. 

Group  III 

9.  On  a  day  when  the  thermometer  stood  at  15°  C.  a  projectile  moving  forward 

with  an  average  velocity  of  1700  ft.  per  sec.  was  heard  by  the  gunner  to 
strike  its  target  5  sec.  after  it  left  the  gun.  What  was  the  distance  from 
the  gun  to  the  target  ? 

Group  IV 

10.  Describe  with  the  aid  of  a  diagram  a  method  for  determining  the  position  and 

size  of  the  image  of  an  object  produced  by  a  plane  mirror. 

11.  c)  What  kind  of  a  mirror  will  produce  an  erect  image  of  an  object  one-half  of 

its  natural  size  when  the  object  is  10  in.  from  the  mirror  ? 

b)  WTiat  is  the  radius  of  curvature  of  the  mirror  ? 

12.  A  candle  is  8  in.  from  a  lens.     Its  real  image  is  40  in.  from  the  lens.     Show 

from  calculation  and  diagram  the  relative  positions  of  lens  image,  and 
object  and  the  relative  sizes  of  the  image  and  the  object. 

Group  V 

13.  A  single  closed  loop  of  wire  lies  in  a  horizontal  plane,  and  through  it  is  dropped 

a  bar  magnet  whose  north  pole  is  pointing  downward. 

a)  Show  by  a  diagram  the  direction  of  the  current  induced  in  the  wire  while 

the  magnet  is  approaching  the  loop  ?     State  the  law  illustrated  by  this 
experiment. 

b)  What  factors  determine  the  magnitude  of  this  current  ? 

14.  A  circuit  consists  of  the  following  four  parts  joined  in  series:  an  ammeter  of 

negligible  resistance;  a  cell  with  an  internal  resistance  of  0.8  ohms;  a  pair 
of  wires,  of  4  ohms  and  6  ohms  resistance  respectively,  joined  in  parallel; 
a  1-ohm  coil.  The  connecting  wires  have  a  resistance  of  0.2  ohm.  Make 
a  labeled  diagram  of  the  circuit. 

a)  If  the  electromotive  force  of  the  cell  is  1 . 4  volts,  what  is  the  reading  of  the 

ammeter  ? 

b)  How  much  current  flows  through  each  of  the  two  wires  which  are  joined  in 

parallel  ? 

15.  An  incandescent  lamp  has  a  resistance  of  275  ohms  when  connected  with  a 

110-volt  circuit. 

a)  If  the  lamp  takes  1 .  25  watts  per  candle  power,  what  is  its  candle  power  ? 

b)  How  much  heat  is  developed  in  the  lamp  per  minute  ? 

I3« 


Pagel 

1920 

Comprehensive  Examination 


PHYSICS 

Friday,  June  25  2-5  p.m. 

Answer  ten  questions  as  indicated  below.  No  extra  credit  will  be  given  for  more  than 
ten  questions. 

Indicate  clearly  your  reasoning  in  each  problem  and  state  the  units  in  which  each 
answer  is  expressed. 

Number  and  letter  each  answer  to  correspond  with  the  question  selected. 

Group  I 
(Omit  one  question  from  this  group) 

1.  a)  Explain  the  principle  of  the  mercury  barometer. 

b)  What  is  the  pressure  in  the  mercury  halfway  up  the  barometer  column  ? 

c)  What  effect  does  the  diameter  of  the  barometer  tube  have  upon  the  height 

of  the  mercury  column  ? 

2.  a)  State  Archimedes'  principle. 

b)  What  application,  if  any,  does  this  principle  have  in  aeronautics  ? 

c)  Since  hydrogen  is  lighter  than  air,  would  pumping  more  and  more  hydrogen 

into  a  balloon  increase  its  lifting  power  ?    Explain  fully. 

3.  A  truck  weighing  4  tons  changes  its  speed  at  a  uniform  rate  from  10  miles 

per  hour  to  20  miles  per  hour  in  2  minutes. 

a)  What  force  is  required  to  produce  this  change  in  speed  ? 

b)  What  distance  does  the  truck  go  in  the  2  minutes  ? 

4.  A  cord  10  feet  long  has  its  ends  fastened  8  feet  apart  on  a  ceiling  and  supports 

a  weight  of  20  pounds  from  its  middle  point.    Find  the  tension  in  the  cord. 

Group  II 
(Omit  one  question  from  this  group) 

5.  a)  When  musical  instruments  are  not  in  exact  imison  one  hears  a  throbbing 

called  "beats."    Explain. 
b)  What  is  meant  by  resonance  ? 

6.  a)  Describe  a  method  for  determining  the  velocity  of  sound  in  air. 

b)  An  open  organ  pipe  is  3.5  feet  long.    What  is  the  frequency  of  its  funda- 
mental tone  ? 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

Group  HI 
(Omit  one  question  from  this  group) 

7.  a)  Describe,  by  the  aid  of  a  diagram,  the  construction  of  a  reciprocating 

steam  engine  and  explain  its  operation. 
h)  In  what  respects  does  the  steam  escaping  from  the   cylinder  of  the 
engine  differ  from  that  entering  it  ? 

8.  Three  pounds  of  water  at  a  temperature  of  50°  F.  are  contained  in  an 

aluminium  kettle  (specific  heat =0.22)  weighing  2  pounds.  If  one  cubic 
foot  of  gas  when  burned  suppHes  600  B.T.U.  how  many  cubic  feet  of  gas 
are  needed  to  turn  one-haK  the  water  in  the  kettle  into  steam,  assuming 
no  loss  of  heat  ?  Consider  the  atmospheric  pressure  to  be  normal.  The 
latent  heat  of  vaporization  of  water =972  B.T.U.  per  pound. 

9.  One  thousand  grams  of  liquid  ammonia  at  0°  C.  enters  the  pipes  of  an  ice- 

making  machine  and  leaves  them  as  gas  at  0°  C.  How  much  water  at 
10°  C.  will  it  change  to  ice  at  0°  C.  ?  The  heat  of  vaporization  of  ammonia 
is  450  calories  per  gram. 

Group  IV 
((Dmit  one  question  from  this  group) 

10.  Explain  the  meaning  of  the  following  terms  used  in  connection  with  light: 

refraction,  index  of  refraction,  critical  angle,  reflection,  dispersion. 

11.  A  tree  55  feet  high  stands  on  the  edge  of  a  pond.     From  the  opposite  bank  a 

man  whose  eyes  are  5 . 5  feet  above  the  level  of  the  pond,  and  who  is  stand- 
ing 18  feet  from  the  edge  of  the  pond,  sees  the  reflected  image  of  the  tree 
with  the  top  appearing  to  just  touch  the  edge  of  the  pond  nearest  to  him. 
How  wide  is  the  pond  ? 

12.  An  image,  10  feet  by  12  feet  in  size,  of  a  lantern  slide,  2.5  inches  by  3  inches 

in  size,  is  thrown  upon  a  screen  40  feet  from  the  lens  of  the  lantern. 
a)  What  is  the  focal  length  of  the  lens  ? 

6)  If  a  larger  image  were  wanted,  should  a  lens  of  greater  or  of  less  focal 
length  be  used  ?    State  reason  for  your  answer. 

Group  V 
{Omit  one  question  from  this  group) 

13.  a)  What  are  the  essential  parts  of  an  alternating  current  generator? 
h)  Describe  its  operation. 

c)  Does  it  create  electrical  energy  ?    Give  reason  for  your  answer. 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  3) 


Page  3 

14.  Electric  power  is  supplied  to  a  kitchen  range  from  110- volt  mains. 

a)  If  the  range  takes  a  current  of  9  amperes,  what  is  the  resistance  of  the 

heating  coil  ? 

b)  If  power  costs  3  cents  per  kilowatt-hour,  how  much  does  it  cost  per  hour 

to  run  the  range  ? 

c)  If  all  the  energy  supplied  were  used  in  heating  water,  how  long  would  it 

take  to  heat  4  kilograms  of  water  from  20°  C.  to  100°  C.  ? 

15.  In  a  certain  experiment  the  current  from  two  dry  cells  in  series  divides  and 

one  part  goes  through  a  wire  100  centimeters  long  having  a  resistance  of 
2.5  ohms,  while  the  other  part  goes  through  two  coils  in  series  with  each 
other,  one  of  4  ohms  resistance  and  the  other  of  6  ohms  resistance, 
o)  Represent  the  scheme  of  connections  by  a  diagram. 
b)  If  each  of  the  dry  cells  has  an  electromotive  force  of  1.4  volts  and  an 
internal  resistance  of  0.2  ohm,  find  the  current  passing  through  the 
100-centimeter  wire  and  the  current  passing  through  the  6-ohm  coiL 


I4t 


Page  1 

1920 
PHYSICS 

Monday,  September  20  2-5  p.m. 

Answer  ten  questions  as  indicated  below.  No  extra  credit  will  be  given  for  more 
than  ten  questions.  Indicate  clearly  your  reasoning  in  each  problem  and  state  the  units 
in  which  each  answer  is  expressed. 

Number  and  letter  each  answer  to  correspond  with  the  question  selected. 

Group  I 
{Oviit  one  question  from  this  group.) 

1.  Describe  the  construction  and  explain  the  operation  of  the  piston  air  pump: 
c)  As  employed  for  exhausting  a  receiver. 

h)  As  employed  for  compressing  air. 

2.  The  density  of  a  piece  of  metal  is  165  pounds  per  cubic  foot. 

a)  What  is  its  specific  gravity  ? 

h)  What  will  a  cubic  centimeter  of  the  metal  weigh  ? 

c)  How  much  will  a  cubic  foot  of  the  metal  weigh  when  immersed  in  alcohol 
of  specific  gravity  0.8  ? 

3.  A  hill  rises  50  feet  in  its  length  of  2,000  feet.     What  horse-power  is  needed  to 

draw  a  load  of  5  tons  at  a  uniform  rate  up  the  hill  in  10  minutes  if  20  per 
cent  of  the  total  work  is  done  against  friction  ? 

4.  a)  A  boy  weighing  50  pounds  is  seated  in  a  swing  supported  by  two  parallel 

ropes  13  feet  long.     How  great  a  horizontal  force  will  be  required  to  hold 
him  5  feet  to  one  side  of  the  vertical  position  ? 

b)  What  will  be  the  tension  then  on  each  of  the  swing  ropes  ? 

Group  II 
{Omit  one  question  from  this  group.) 

5.  Given  a  tuning-fork  making  256  vibrations  per  second,  how  could  you  deter- 

mine the  velocity  of  sound  by  means  of  a  resonating  column  of  air  ? 

6.  a)  How  would  the  intensity  of  the  sound  of  a  bell  heard  by  a  man  1,000  feet 

away  compare  with  the  intensity  of  the  sound  heard  by  a  man  2,500  feet 
away? 
b)  If  the  tone  of  a  man's  voice  has  a  frequency  of  100,  how  long  are  the  waves 
which  are  produced  when  he  speaks  in  air  at  a  temperature  of  20°  C.  ? 

Group  III 
{Omit  one  question  from  this  group.) 

7.  a)  How  does  change  of  pressure  aflfect  the  melting-point  of  ice  or  the  freezing- 

point  of  water  ? 

b)  How  do  the  boiling-point  and  the  freezing-point  of  salt  water  differ  from 

those  of  pure  water  ? 

c)  How  is  the  boiling-point  of  water  affected  by  change  of  pressure  ? 

(THIS  EXAMINATION  IS  CONTINUED  ON  PAGE  2) 


Page  2 

8.  A  stove  burning  150  grams  of  alcohol  changes  4,500  grams  of  ice  at  0°  C.  into 

water  at  100°  C.  in  10  minutes.  If  the  heat  of  combustion  of  alcohol  is 
7,400  calorics  per  gram,  what  per  cent  of  the  heat  produced  is  utilized  ? 

9.  a)  What  is  meant  by  the  absolute  zero  ? 

b)  From  what  point  on  the   Centigrade  scale  are  absolute  temperatures 

measured  ? 

c)  Two  liters  of  air  at  atmospheric  pressure  and  at  20°  C.  are  heated  until 

the  volume  and  the  pressure  are  both  doubled.     What  is  the  tempera- 
ture of  the  air  ? 

Group  IV 
(Omit  one  question  from  this  group.) 

10.  a)  Distinguish  carefully  between  refraction  and  dispersion. 

b)  Why  does  a  very  thin  layer  of  oil  on  water  produce  colors  ? 

c)  What  is  total  reflection  ? 

d)  What  is  the  critical  angle  ? 

11.  Two  shadows  of  an  upright  rod  are  cast  side  by  side  upon  a  screen,  one  by  a 

standard  candle  and  the  other  by  a  Welsbach  gas  burner.  The  standard 
candle  is  placed  2  feet  from  the  screen.  When  the  gas  burner  is  moved 
until  the  two  shadows  are  of  the  same  density  the  burner  is  found  to  be 
14  feet  from  the  screen.     What  is  the  candle-power  of  the  gas  burner  ? 

12.  An  incandescent  lamp  is  placed  8  feet  from  a  concave  spherical  mirror.     If 

the  image  of  the  lamp  is  seen  1  foot  in  front  of  the  mirror : 
c)  What  is  the  radius  of  curvature  of  the  rriirror  ? 

b)  Is  the  image  real  or  virtual  ? 

c)  What  are  the  relative  sizes  of  the  image  and  of  the  object  ? 

Group  V 
(Omit  one  question  from  this  group.) 

13.  a)  Explain  how  an  electroscope  might  be  given  either  a  positive  or  a  negative 

charge  by  means  of  a  positively  charged  body. 
b)  Describe  the  construction  and  explain  the  operation  of  a  condenser  as 
illustrated  by  a  Leyden  jar. 

14.  a)  A  motor  takes  8  amperes  from  a  500- volt  circuit  and  delivers  5  horse-power. 

What  is  its  efficiency  ? 
b)  An  ammeter  in  circuit  with  a  small  motor  indicates  7  amperes  when  the 
motor  is  starting  and  3.5  amperes  when  the  motor  is  running  at  full 
speed.    Explain. 

15.  A  resistance  coil  marked  10  ohms  is  found  by  careful  measurement  to  have  a 

resistance  of  10.8  ohms.  How  much  wire  whose  resistance  is  1.35  ohms 
per  foot  would  be  needed  and  how  should  it  be  connected  with  the  coil  in 
order  that  the  resistance  of  the  combination  should  be  10  ohms  ? 


M3 


4 


ZOOLOGY 


1^5 


1916 
ZOOLOGY 

Friday  9:00  a.m.    Two  hours 

A  teacher's  certificate  covering  the  laboratory  instruction  must  be  presented  as  part 
of  the  examination. 

Answer  three  questions  from  each  group,  and  one  additional  question  which  may  be 
selected  from  any  group. 

Group  I 

1.  What  structures  in  addition  to  a  backbone  are  characteristic  of  vertebrates 

as  contrasted  with  invertebrates  ? 

2.  Describe  as  completely  as  you  can  the  anatomy,  external  and  internal,  of  an 

annelid  worm. 

3.  Describe  the  component  parts  of  the  blood  of  any  animal,  stating  the  function 

of  each  part. 

4.  Compare  the  respiratory  organs  of  an  insect,  fish,  and  mammal.     Explain 

the  function  of  these  organs. 

5.  Compare  the  skeleton  of  the  leg  and  pelvic  girdle  of  a  man  and  of  a  frog. 

Group  II 

6.  Name  an  animal  belonging  to  each  of  the  following  groups:   coelenterata, 

annelida,  Crustacea,  insecta,  amphibia.     What  is  the  food  of  each  of  the 
animals  you  have  named,  and  how  is  the  food  secured  ? 

7.  Select  some  Protozoan  and  describe:   (a)  its  habitat;  (b)  its  manner  of  food- 

getting;   (c)  its  method  of  locomotion;   (d)  its  method  of  reproduction. 

8.  Distinguish  between  the  inhaling  process  in  the  frog  and  in  man. 

9.  Describe  the  circulation  of  blood  in  a  fish. 

10.  Describe  the  life-cycle  of  a  frog  and  show  how  this  animal  is  adapted  to  its 

environment  in  each  stage  of  its  development. 

Group  III 

11.  Name  three  injurious  insects  with  the  methods  for  the  control  of  each. 

12.  What  is  the  actual  evidence  that  certain  birds  are  beneficial  to  the  farmer  ? 

13.  Name  some  wild  animal  that  it  would  be  worth  while  to  try  to  domesticate, 

and  give  the  reasons  why. 

14.  What  can  be  done  to  prevent  malaria  and  yellow  fever  ?     Explain  the  reasons 

for  your  answer. 

15.  What  is  being  done  to  increase  our  supply  of  food  fishes  ? 


146 


^ 


1917 

ZOOLOGY 

Friday  2  p.m.     Two  hours 

Answer  three  questions  from  each  group,  and  one  additional  question  which  may  be 
selected  from  any  group. 

Group  I 

1.  Describe  the  structure  of  any  protozoan  you  have  studied,  stating   the 

function  of  each  of  its  parts. 

2.  (a)  Name  and  locate  the  appendages  of  the  crayfish  or  of  the  lobster  and 

state  the  functions  oijive  dillcrent  appendages  named,  or  (b)  Draw  and 
name  the  mouth  parts  of  some  insect. 

3.  Describe  the  structure  of  the  eye  of  some  vertebrate  and  explain  how  the 

phenomenon  of  sight  occurs. 

4.  Compare  the  nervous  system  of  man  with  that  of  some  invertebrate. 

5.  Compare  the  organs  of  excretion  of  three  of  the  following:  (a)  an  annelid, 

(6)  an  insect,  (c)  a  crustacean  or  mollusk,  (d)  a  fish  or  frog,  (e)  a  bird  or 
mammal. 

Group  II 

6.  Describe  the  complete  course  of  a  molecule  of  oxygen  from  the  external  air 

to  the  brain  of  an  animal. 

7.  Give  the  characteristics  that  assign: 

(a)  a  beetle  to  its  order; 

(b)  a  crayfish  to  its  class; 

(c)  an  ameba  to  its  branch  or  phylum; 

(d)  a  spider  to  its  class; 

(e)  a  fly  to  its  branch  or  phylum. 

8.  Give  the  life  history  of  an  insect  having  complete  metamorphosis. 

9.  Explain  the  process  of  fertilization  and  the  first  divisions  of  the  egg  in  some 

animal. 

10.  Explain  the  process  of  digestion  of  food  in  a  mixed  diet. 

Group  III 

11.  Describe  the  economic  importance  of  five  of  the  following  animals:  mosquito, 

house  fly,  trichina,  starfish,  clam,  earthworm,  toad,  cuckoo,  weasel. 

12.  Mention  two  external  and  two  internal  animal   parasites  of   man   or  of 

domestic  animals,  giving  for  each  the  source  from  which  infestation  occurs. 

13.  What  steps  are  taken  by  the  national,  or  your  state  government  to  protect 

and  to  increase  the  numbers  of  valuable  fishes  or  birds  ? 

14.  (a)  In  what  ways  are  the  codUng  moth  and  the  English  sparrow  pests  ? 
(6)  How  may  each  be  controlled  ? 

15.  (a)  Give  an  outline  of  the  life  history  of  the  malarial  parasite. 

(b)  State  the  agency  by  means  of  which  infection  occurs. 

(c)  What  are  the  methods  of  preventing  malaria? 

147 


1918 
ZOOLOGY 

Friday,  June  21  2  p.m.     Two  hours 

Answer  three  questions  from  each  group,  and  one  additional  question  which  may  be 
selected  from  any  group. 

Group  I 

1.  Describe  fully  the  organs  used  by  some  insect  in  the  process  of  breathing,  and 

explain  how  these  organs  work. 

2.  Compare   the   general  plan  of   the  body  structure   of  a  coelenterate,  an 

annelid,  and  a  vertebrate, 

3.  Describe  the  sense  organs  of  (a)  an  annelid,  (b)  an  insect,  (c)  a  crayfish  or  a 

mollusk,  and  (d)  a  fish  or  a  frog,  explaining  the  function  of  each. 

4.  Explain  with  diagrams  the  cell  structure  of  (a)  bone,  (&)  muscle,  and  (c)  blood. 

5.  Compare  the  characteristic  method  of  locomotion  and  the  organs  concerned 

in  a  fish,  a  frog,  and  a  bird. 

Group  II 

6.  Describe  the  processes  oi  reproduction  and  regeneration  in  Hydra. 

7.  Define  each  of   the    following    terms   and    give    an    example    of   its   use: 

(g)  parasitism,  (b)  protective  resemblance,  (c)  segmentation,  (d)  special- 
ization, (e)  struggle  for  existence. 

8.  Illustrate  by  concrete  example  what  is  meant  by  Mendel's  Law  of  Heredity. 

9.  (a)  Describe  the  life  cycle  of  the  mosquito. 
{b)  What  is  the  food  of  this  insect  ? 

(c)  What  are  its  enemies  ? 

(d)  What  is  its  importance  to  nian  ? 

10.  Describe  in  detail  the  various  steps  that  take  place  from  the  time  that  the  egg 

cells  and  sperm  cells  of  a  fish,  or  a  frog,  are  deposited  in  the  water  until 
the  gastrula  stage  is  formed. 

Group  III 

11.  Give  the  life-history  of  a  protozoan  that  lives  in  human  blood. 

12.  What  is  the  principal  food  of  five  of  the  following  birds  and  how  does  each 

secure  it:  woodpecker,  owl,  robin,  quail,  humming-bird,  English  sparrow, 
chickadee  ? 

13.  If  you  were  a  fruit  farmer,  what  animals  would  you  try  to  secure  on  your 

farm  and  what  animals  would  you  try  to  exterminate  ?     Give  reasons. 

14.  Name  three  animal  parasites  that  cause  human  disease.     Show  in  each 

instance  the  method  of  infection  and  the- means  of  prevention. 

15.  Describe  methods  by  which  the  supply  of  available  animal  food  for  man  may 

be  increased  in  the  United  States. 
I4» 


Page  1 

1919 

ZOOLOGY 

Friday,  June  20  2  p.m.     Two  hours 

Answer  three  questions  from  each  group,  and  one  additional  question  which  may  be 
selected  from  any  group.    Nxunber  each  answer  to  correspond  with  the  question  selected. 


Group  I 

1.  Make  a  labeled  drawing  of  the  alimentary  canal  of  a  bird  or  of  a  fish. 

2.  Describe,  or  illustrate  by  a  carefully  labeled  diagram,  the  mouth  parts  of  an 

insect,  stating  the  function  of  each  organ. 

3.  Explain  the  structure  of  the  human  stomach  and  describe  the  work  which  this 

organ  performs,  stating  the  effect  on  foodstuffs  of  each  of  its  secretions 

4.  How  are  homologous  structures  adapted  to  diverse  uses  in  the  human  hand 

and  foot? 

5.  In  connection  with  the  frog  name  and  locate:  (a)  two  types  of  joints,  (b)  two 

types  of  muscles,  {c)  two  ductless  glands,  (d)  two  kinds  of  nerves,  (e)  two 
digestive  glands. 

Group  II 

6.  Account  for  five  of  the  following  facts  and  indicate  in  each  instance  the  animal 

concerned: 

a)  Larger  nimiber  of  sperms  than  eggs. 

b)  Open  valve  in  dead  bivalve  molluscs. 

c)  Absence  of  gills  in  certain  aquatic  animals. 

d)  Absence  of  mouth  parts  in  certain  adult  animals. 

e)  Dentition  with  cusps. 

/)  Degenerate  vermiform  appendix. 

7.  Describe  the  reproduction  of  Paramecium. 

8.  Define  each  of  the  following  terms:    (a)  natural  selection,  (b)  Mendelism, 

(c)  anesthetics,  (d)  trichinosis,  (c)  flagellum,  (/)  hermaphroditic,  (g)  reflex, 
(h)  gastrula,  (i)  asexual,  (J)  respiration. 

9.  Describe  the  development  of  the  frog  or  toad  from  the  time  of  egg-laying  to 

the  adult  stage. 

10.  (a)  What  nutrients  are  needed  in  a  normal  diet  ? 

(6)  State  the  principal  use  to  the  organism  of  each  nutrient  mentioned. 

(THIS  EXAMINATION  IS  CONTINUED   ON  PAGE  2) 

M9 


Page  2 

Group  III 

11.  Indicate  the  important  methods  employed  by  the  government  for  the  pro- 

tection and  propagation  of  food  fishes. 

12.  (ja)  Name  three  kinds  of  animals  that  have  definitely  aided  man  in  the  war, 

and  show  how  each  has  been  of  service. 
{h)  Name  three  kinds  of  animals  which  have  been  a  hindrance  to  man  in  war 
time.     Explain. 

13.  (a)  Name  two  or  more  kinds  of  birds  useful  in  each  case  in  destroying  (1)  in- 

sects, (2)  weeds,  (3)  rodents. 
{b)  Give  a  general  summary  of  methods  of  bird  protection. 

14.  What  was  the  wild  ancestor  of  each  of  the  following  animals:    {a)  dog, 

(6)  homing  pigeon,  (c)  domestic  hen,  {d)  pig  ? 

15.  How  do  the  following  insects  afifect  man:  (a)  Anopheles  mosquitoes,  (6)  lady- 

bird beetles,  (c)  house  flies,  {d)  cabbage  butterflies,  (e)  grasshoppers? 


150 


1920 
ZOOLOGY 

Friday,  June  25  2  p.m.     Two  hours 

Answer  three  questions  from  each  group,  and  one  additional  question  which  may  be 
selected  from  any  group.     Number  each  answer  to  correspond  with  the  question  selected. 

Group  I 

1 .  Make  a  labeled  drawing  of  the  brain  of  some  vertebrate  and  state  the  function 

of  each  part. 

2.  Compare  the  body-plan  of  coelenterate,  annelid,  insect,  and  vertebrate. 

3.  Describe  the  composition  of  the  blood  and  explain  what  changes  it  undergoes 

in  the  lungs. 

4.  Describe  with  as  much  detail  as  possible  some  protozoan  which  you  have 

studied  in  the  laboratory. 

5.  Name  and  locate  the  different  kinds  of  cells  found  in  the  human  hand. 

Group  II 

6-  Indicate  the  location  of  each  of  the  following  and  discuss  its  particular 

function  in  animals:    haemoglobin,  pepsin,  leucocyte,  dentine,  epithehum. 

7-  Explain  briefly  Mendel's  laws  of  heredity. 

8.  Describe  the  methods  of  reproduction  and  regeneration  in  Hydra. 

9.  Name  two  animals  that  meet  winter  conditions,  (a)  by  hibernating;    (b)  by 

migrating;  (c)  by  remaining  active.  Give  reasons  for  each  of  these  differ- 
ences in  behavior, 

10.  Name  the  great  branches  or  phyla  of  the  animal  kingdom  and  the  important 

classes  under  each. 

Group  III 

11.  Name  the  principal  animal  parasites  of  man,  and  explain  how  each  is  injurious. 

12.  Name  some  animal  of  economic  importance  in  connection  with  each  of  the 

following  articles  of  human  use:  cloth,  varnish,  leather,  buttons,  oil. 

13.  How  may  insect  pests  be  controlled  by  the  use  of  other  insects  ? 

14.  Mention  the  princijial  food  of  each  of  the  following:    black  snake,  toad, 

pickerel,  cicada,  earthworm,  bumblebee,  starfish,  skunk,  gipsy  moth,  crow. 
Which  of  these  animals  should  be  protected  and  which  should  be 
exterminated  ? 

15.  Name   eight   animals,   each   belonging   to   a   different   order,    that   are   of 

importance  as  human  food. 

151 


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